DOE-HDBK-1122-2009 Chg Notice 2, Radiological Control Technician Training (Part 3 of 9)
Functional areas: Radiological Control Technician, Instructors Guide, Radiological Control
This Handbook describes an implementation process for core training as recommended in chapter 14 to Implementation Guide G441.1-1C , Radiation Protection Programs for Use with Title 10, Code of Federal Regulations, Part 835, Occupational Radiation Protection, and as outlined in the DOE standard, Radiological Control (RCS). The Handbook is meant to assist those individuals within the Department of Energy, Managing and Operating contractors, and Managing and Integrating contractors identified as having responsibility for implementing core training recommended by the RCS
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- DOE-HDBK-1122-2009 Chg Notice 2Radiological Control Technician Training (Part 1 of 9, links to all Parts)
- DOE-HDBK-1122-2009 Chg Notice 2Radiological Control Technician Training (Part 2 of 9)
- DOE-HDBK-1122-2009 Chg Notice 2Radiological Control Technician Training (Part 4 of 9)
- DOE-HDBK-1122-2009 Chg Notice 2Radiological Control Technician Training (Part 5 of 9)
- DOE-HDBK-1122-2009 Chg Notice 2Radiological Control Technician Training (Part 6 of 9)
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- DOE-HDBK-1122-2009 Chg Notice 2Radiological Control Technician Training (Part 8 of 9)
- DOE-HDBK-1122-2009 Chg Notice 2Radiological Control Technician Training (Part 9 of 9)
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Section 1
Part 3 of 9
Radiological Control Technician Training
Fundamental Academic Training Instructor’s Guide Phase I
Coordinated and Conducted
for the
Office of Health, Safety and Security
U.S. Department of Energy
DOE-HDBK-1122-2009
Radiological Control Technician Instructor’s Guide
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Radiological Control Technician Instructor’s Guide
Table of Contents
Page
Module 1.01 Basic Mathematics and Algebra……………………………………………... 1.01-1
Module 1.02 Unit Analysis and Conversion……………………………………………….. 1.02-1
Module 1.03 Physical Sciences……………………………………………………………..1.03-1
Module 1.04 Nuclear Physics……………………………………………………………… 1.04-1
Module 1.05 Sources of Radiation………………………………………………………….1.05-1
Module 1.06 Radioactivity and Radioactive Decay……………………………………….. 1.06-1
Module 1.07 Interaction of Radiation with Matter………………………………………… 1.07-1
Module 1.08 Biological Effects of Radiation……………………………………………… 1.08-1
Module 1.09 Radiological Protection Standards…………………………………………... 1.09-1
Module 1.10 ALARA……………………………………………………………………… 1.10-1
Module 1.11 External Exposure Control…………………………………………………... 1.11-1
Module 1.12 Internal Exposure Control…………………………………………………… 1.12-1
Module 1.13 Radiation Detector Theory…………………………………………………... 1.13-1
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Radiological Control Technician Instructor’s Guide
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DOE-HDBK-1122-2009
Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
Course Title: Radiological Control Technician
Module Title: Basic Mathematics and Algebra
Module Number: 1.01
Objectives:
1.01.01 Add, subtract, multiply, and divide fractions.
1.01.02 Add, subtract, multiply, and divide decimals.
1.01.03 Convert fractions to decimals and decimals to fractions.
1.01.04 Convert percent to decimal and decimal to percent.
1.01.05 Add, subtract, multiply, and divide signed numbers.
1.01.06 Add, subtract, multiply, and divide numbers with exponents.
1.01.07 Find the square roots of numbers.
1.01.08 Convert between numbers expressed in standard form and in scientific notation.
1.01.09 Add, subtract, multiply, and divide numbers expressed in scientific notation.
1.01.10 Solve equations using the "Order of Mathematical Operations."
1.01.11 Perform algebraic functions.
1.01.12 Solve equations using common and/or natural logarithms.
References:
1. DOE-HDBK-1014/1-92 (June 1992) "Mathematics: Volume 1 of 2"; DOE Fundamentals
Handbook Series.
Instructional Aids:
1. Overheads
2. Overhead projector/screen
3. Chalkboard/whiteboard
4. Lessons learned
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Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
I. MODULE INTRODUCTION
A. Self Introduction
1. Name
2. Phone number
3. Background
4. Emergency procedure review
B. Motivation
Radiological control operations frequently require the RCT to use
arithmetic and algebra to perform various calculations. These include
scientific notation, unit analysis and conversion, radioactive decay
calculations, dose rate/distance calculations, shielding calculations,
and stay-time calculations. A good foundation in mathematics and
algebra is important to ensure that the data obtained from calculations
is accurate. Accurate data is crucial to the assignment of proper
radiological controls.
C. Overview of Lesson
1. Fractions
2. Decimals
3. Percent
4. Signed Numbers
5. Exponents
6. Square Roots
7. Scientific Notation
8. Order of Mathematical Operations
Section 2
9. Algebra
10. Logarithms
O.H.: Objectives
D. Introduce Objectives
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II. MODULE OUTLINE
A. Symbols for Basic Operations
See Table 1. -
1. The four basic mathematical operations are addition, subtraction, "Symbols for Basic
multiplication, and division. Furthermore, it is often necessary to Mathematical
group numbers or operations using parentheses or brackets. In Operations"
writing problems in this course the notation shown in Table 1 is
used to denote the operation to be performed on the numbers.
Objective 1.01.01
B. Fractions
1. Whole numbers consist of the normal counting numbers and zero.
{e.g., 0, 1, 2, 3, 4...}
2. A fraction is part of a whole number. It is simply an expression of
a division of two whole numbers. A fraction is written in the
format:
a or a/b
b
a. The number above the bar a is called the numerator and the
number below the bar b is called the denominator. A proper
fraction is a fraction in which the number in the numerator is
less than the number in the denominator. If the numerator is
greater than the denominator then it is an improper fraction.
For example, ½ and ¼ are proper fractions, while, 25/5, 15/7,
or 61/27 are improper fractions.
b. Any whole number can be written as a fraction by letting the
whole number be the numerator and 1 be the denominator.
For example:
5 2 05 = 2 = 0 =
1 1 1
c. Five can be written as 10/2, 15/3, 20/4, etc. Similarly, the
fraction ¼ can be written as 2/8, 3/12, 4/16, etc. These are
called equivalent fractions. An equivalent fraction is built up,
per se, by multiplying the numerator and the denominator by
the same non-zero number. For example:
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Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
3 3×2 6 3 3×5 15
= = = =
4 4 ×2 8 4 4 ×5 20
d. A fraction is reduced by dividing the numerator and the
denominator by the same non-zero number. For example:
12 12 ÷2 6 6 6 ÷3 2
= = = =
18 18 ÷ 2 9 9 9 ÷3 3
e. A fraction is reduced to lowest terms when 1 is the only
number that divides both numerator and denominator evenly.
This is done by finding the greatest common multiple between
the numerator and denominator. In the previous example, two
successive reductions were performed. For the fraction 12/18,
the greatest common multiple would be 6, or (2 × 3), which
results in a reduction down to a denominator of 3.
f. A whole number written with a fraction is called a mixed
number. Examples of mixed numbers would be 1½, 3¼, 5¾,
etc. A mixed number can be simplified to a single improper
fraction using the following steps:
1) Multiply the whole number by the denominator of the
fraction.
2) Add the numerator of the fraction to the product in step 1.
2) Add the numerator of the fraction to the product in step 1.
3) Place the sum in step 2 as the numerator over the
denominator.
4) Example:
( )× + 3 23 3 5 4
5 = =
4 4 4
3. Adding and Subtracting Fractions
a. Fractions with the Same Denominator
1) To add two fractions which have the same denominator:
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a) Add the numerators
b) Place the sum of step 1 over the common denominator
c) Reduce fraction in step 2 to lowest terms (if
necessary)
2) Example:
1 3 1+ 3 4
+ = =
5 5 5 5
3) Subtraction of two fractions with the same denominator is
accomplished in the same manner as addition. For
example:
Section 3
5 3 5 −3 2 2 ÷ 2 1
− = = = =
8 8 8 8 8 ÷ 2 4
b. Fractions with Different Denominators
1) To add two fractions with different denominators requires
that the fractions be built up so that they have the same
denominator. This is done by finding the lowest common
denominator. Once a common denominator is obtained,
the rules given above for the same denominator apply.
2) For example, 1/3 + 2/5. The fraction 1/3 could be built up
to 2/6, 3/9, 4/12, 5/15, 6/18, 7/21, etc. The fraction 2/5
could be built up to 4/10, 6/15, 8/20, 10/25, etc. The
lowest common denominator for the two fractions would
be 15. The problem would be solved as follows:
1 2 1×5 2×3 5 6 11
+ = + = + =
3 5 3×5 5×3 15 15 15
3) Subtraction of fractions with different denominators is
accomplished using the same steps as for addition. For
example:
3 2 3×3 2×4 9 8 1
− = − = − =
4 3 4×3 3×4 12 12 12
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4. Multiplying and Dividing Fractions
a. Multiplication of fractions is much easier than addition and
subtraction, especially if the numbers in the numerators and
denominators are small. Fractions with larger numerators
and/or denominators may require additional steps. In either
case, the product of the multiplication will most likely need to
be reduced in order to arrive at the final answer. To multiply
fractions:
1) Multiply the numerators.
2) Multiply the denominators.
3) Place product in step 1 over product in step 2.
4) Reduce fraction to lowest terms.
5) Example:
5 3 5×3 15 15 ÷3 5
× = = = =
6 4 6×4 24 24 ÷3 8
b. A variation on the order of the steps to multiply fractions is to
factor the numerators and denominators first, reduce and
cancel, and then multiply. For example:
3 20 3 2× ×2 5 3 2 2 5 5× × × 5
× = × = = =
8 9 × × 3×3 2 2 2 3 3 2×32 2 2 × × × × 6
5. Reciprocals
a. Two numbers whose product is 1 are called reciprocals, or
multiplicative inverses. For example:
1 1
1) 5 and are reciprocals because 5× =1
5 5
4 5 4 5
2) and are reciprocals because × =1
5 4 5 4
3) 1 is its own reciprocal because 1 1× =1
4) 0 has no reciprocal because 0 times any number is 0 not 1
b. The symbol for the reciprocal, or multiplicative inverse, of a
1
non-zero real number a is .
a
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Every real number except 0 has a reciprocal. Therefore, for
every non-zero real number a, there is a unique real number
1
such that
a
1 a × =1
a
c. Now, look at the following product:
⎛ 1 1 ⎞ ⎛ 1 ⎞⎛ 1 ⎞( )⎜ ⎟ ⎜ a × ⎟⎜b× ⎟ =1 1 =1ab × = ×
⎝ a b ⎠ ⎝ a ⎠⎝ b ⎠
6. Relationship of multiplication to division
a. The operation of division is really just inverted multiplication
(reciprocals). Notice from the above examples the reciprocal
of a fraction is merely "switching" the numerator and
denominator. The number 5 is really 5/1, and the reciprocal
of 5 is 1/5. Likewise, the reciprocal of 2/3 is 3/2.
b. Fractions are a division by definition. Division of fractions is
accomplished in two steps:
1) Invert the second fraction, i.e., change it to its reciprocal,
and change the division to multiplication.
2) Multiply the two fractions using the steps stated above.
3) Examples:
(1/2)/3 = 1 / (2/3) = 1 x 3/2 = 3/2
C. Decimals
Section 4
1. A decimal is another way of expressing a fraction or mixed
number. It is simply the numerical result of division (and
fractions are division). Recall that our number system is based on
10 ("deci" in "decimal" means ten) and is a place-value system;
that is, each digit {i.e., 0, 1, 2, 3, 4, 5, 6, 7, 8, 9} in a numeral has
a particular value determined by its location or place in the
number. For a number in decimal notation, the numerals to the
left of the decimal point comprise the whole number, and the
numerals to the right are the decimal fraction, (with the
denominator being a power of ten).
Objective 1.01.02
See Fig. 1 -
"Decimal Places"
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2. For example, the numeral 125.378 (decimal notation) represents
the expanded numeral:
3 7 8100 + 20 + 5 + + +
10 100 1000
3. If this numeral were written as a mixed number, we would write it
as:
378125
1000
4. Addition and Subtraction of Decimals
a. In order to add or subtract decimals use the following steps:
1) Arrange the numbers in a column so that the decimal
points are aligned.
2) Add or subtract in columns from right to left. (Additional Subtrahend - a
zeros may need to be added to the right of the number that is to be
subtrahend.) subtracted from the
minuend).
3) Place the decimal point in the answer in line with the
other decimal points.
4) Examples:
21.3 654.200
+4.2 -26.888
25.5 627.312
5. Multiplying Decimals
a. To multiply decimal numbers, do the following:
1) Multiply the numbers as if there were no decimal points.
2) Count the number of decimal places in each number and
add them together.
3) Place the decimal point in the product so that it has the
same number of decimal places as the sum in step 2.
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Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
4) Examples:
5.28
×3.7
3696
1584
19.536
0.04
×0.957
028
020
036
000
0.03828
6. Division of Decimals
a. The steps for division of decimals are as follows:
1) Move the decimal point of the divisor to the right until it
becomes a whole number.
2) Move the decimal point of the dividend to the right the
same number of places moved in step 1.
Divisor - The
number by which a
dividend is divided.
Dividend - a number
to be divided.
3) Divide the numbers as if they were whole numbers.
4) Example:
28
0
200
200
50
0.25 7.00
7. Decimal Forms
a. As we have learned, decimals are the result of division (or a
fraction). When the remainder of the division is zero, the
resulting decimal is called a terminating or finite decimal.
For example, fractions like 2/5, 3/8, and 5/6 will all result in
finite decimals. These fractions and the resulting decimals are
known as rational numbers.
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b. On the other hand, fractions like 1/3, 2/7, 5/11, and 7/13 result
in a non-terminating or infinite decimal. For example, 2/7
results in the decimal 0.285714286 . . . , the dots meaning that
the decimal continues without end. These numbers are known
as irrational numbers. Note that even though irrational
numbers are non-terminating, some (e.g., 1/3 and 5/11) are
repeating or periodic decimals because the same digit or block
of digits repeats unendingly. For example:
1 5
= 0.3333... = 0.454545...
3 11
c. A bar is often used to indicate the block of digits that repeat,
as shown below:
Section 5
1 5
= 0.3 = 0.45
3 11
D. Fraction to Decimal Conversion Objective 1.01.03
To convert a fraction to a decimal we simply perform the operation of
division that the fraction represents. For example, the fraction 3/4
represents "3 divided by 4," and would be converted as follows:
0.75
4 3.00
28
20
20
0
E. Percent Objective 1.01.04
1. Percentage is a familiar and widely used concept for expressing
common and decimal fractions. Most people know the meaning
of terms such as 100 percent and 50 percent. The word percent
actually means "out of a hundred." (Consider that there are 100
"cents" in a dollar, and that a "century" is 100 years.) A percent is
simply a fraction whose denominator is 100. Thus, 50 percent
means 50/100, or 0.50, while 25 percent means 25/100, or 0.25.
2. Percent is abbreviated by the symbol %. So, 75 percent is written
75%.
3. Converting Decimal to Percent
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a. A decimal fraction is changed to a percent by moving the
decimal point two places to the right and adding a percent
sign. For example, 1/8 equals 0.125. Therefore:
1 0.125 = 12.5%= rr8
b. A percent is changed to a common fraction by omitting the
percent sign, placing the number over 100, and reducing the
resulting fraction if possible. For example, 32% equals
32/100 which reduces to 8/25. When the percent consists of a
mixed decimal number with a percent sign, the resulting
fraction will contain a mixed decimal numerator. This can be
changed to a whole number by multiplying the numerator and
the denominator by 10, 100, 1,000, etc. For example:
40.25 40.25×100 4025 80540.25% = = = =
100 100×100 10,000 2000
c. Percentage is most frequently used to indicate a fractional
part. Thus 20% of the total power output for 75% of the
employees refer to fractional parts of some total number. To
perform arithmetic operations with a percent, it is normally
changed to a common or decimal fraction. Usually, a decimal
fraction is more convenient.
4. Converting Percent to Decimal
a. A percent is changed to a decimal fraction by omitting the
percent sign and moving the decimal point two places to the
left. For example:
48% = 0.48ss
b. Thus, 92% equals 0.92, 8% equals 0.08, and so on.
F. Signed Numbers
1. The numbers that are used to quantify the number of objects in a
group, the "counting numbers," are always positive numbers; that
is, they are always greater than zero. However, there are many
occasions when negative numbers (numbers less than zero) must
be used. These numbers arise when we try to describe
measurement in a direction opposite to the positive numbers. For
example, if we assign a value of +3 to a point which is 3 feet
above the ground, what number should be assigned to a point
which is 3 feet below the ground? Perhaps the most familiar
example of the use of negative numbers is the measurement of
temperature, where temperatures below an arbitrary reference
level are assigned negative values.
1.01 - 11
Objective 1.01.05
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Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
2. Every number has a sign associated with it. The plus (+) sign
indicates a positive number, whereas the minus (-) sign indicates a
negative number. When no sign is given, a plus sign (+) is
implied. The fact that the plus and minus signs are also used for
the arithmetic operations of addition and subtraction should not be
a cause for confusion, for we shall see that they have equivalent
meanings.
Section 6
3. Every number has an absolute value, regardless of its sign. The
absolute value indicates the distance from zero, without regard to
direction. The number 5 is 5 units from zero, in the positive
direction. The number -5 is also 5 units from zero, but in the
negative direction. The absolute value of each of these numbers is
5. The absolute value of a number is indicated by a pair of
vertical lines enclosing the number:
5 .
4. Operations with Signed Numbers
See Fig. 2 -
a. The arithmetic operations of addition, subtraction, "Number Line"
multiplication, and division of signed numbers can be more
easily visualized if the numbers are placed on a number line.
The positive numbers are greater than zero, and they lie to the
right of zero on the number line. The negative numbers are
less than zero, and lie to the left of zero on the number line.
b. The number line extends an infinite distance in each direction
and therefore includes all numbers. The process of addition
can be considered as counting in one direction or the other
from a starting point on the number line. For example, let us
add 1 + 2. We locate +1 on the number line and then count 2
units to the right, since we are adding +2. The result will be
+3. To illustrate further, let us add +2 and -4. We first locate
+2 on the number line and then count 4 units to the left. We
end up at -2.
c. The number line is useful for illustrating the principles of
addition, but it clearly would be inconvenient to use in the
case of large numbers. Consequently, the following rules
were developed to govern the addition process.
5. Adding and Subtracting Signed Numbers
a. To add two numbers with the same signs, add their absolute
values and attach the common sign. For example:
(-3) + (-2) = -5
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b. To add two numbers with opposite signs, find the difference
of their absolute values, then attach the sign of the original
number which had the greater absolute value. For example:
(-2) + 3 = 1
c. Notice that -3 and +3 are the same distance but in opposite
directions from 0 on the number line. What happens when
you add two numbers like 3 and -3?
3 + (-3) = 0
−7 + 7 = 0
d. If the sum of two signed numbers is 0, the numbers are called
additive inverses or opposites. For example:
7 - 3 = 4 is the same as: 7 + (-3) = 4
8 - 2 = 6 is the same as: 8 + (-2) = 6
e. It can be seen that subtracting a number is equivalent to
adding its additive inverse or opposite.
f. To subtract a signed number, add its opposite or additive
inverse. In other words, change the subtraction symbol to
addition and change the sign of the second signed number.
For example:
5 - (-8) = 5 + (+8) « add +8
(Answer = 13)
6 - 11 = 6 + (-11) « add -11
(Answer = -5)
−4 - (-7) = -4 + (+7) « add +7
(Answer = 3)
6. Multiplying and Dividing Signed Numbers
a. The product of two numbers with like signs is a positive
number. The product of two numbers with unlike signs is a
negative number. In symbols:
(+) × (+) = (+)
(+) × (-) = (-)
(-) × (-) = (+)
(-) × (+) = (-)
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b. Examples:
(-4) × (-3) = (+12)
(-4) × (+3) = (-12)
c. The division of numbers with like signs gives a positive
quotient. The division of numbers with unlike signs gives a
negative quotient. In symbols:
(+)/(+) = (+)
Section 7
(+)/(-) = (-)
(-)/(-) = (+)
(-)/(+) = (-)
d. Examples:
(-24)/(-6) = (+4)
(-24)/(+6) = (-4)
e. Remember that multiplication is really a short form of
addition. When we say +4 × (3), we are adding the number
3 four times, that is, (-3) + (-3) + (-3) + (-3) = -12. Also,
since division is a short form of subtraction, when we say
24 ÷ (-6), we subtract the number -6 from the number -24 four
times in order to reach 0,
i.e., -24 - (-6) - (-6) - (-6) - (-6) = 0. Although we could
repeat the process for the multiplication and division of any
signed numbers, usage of the two rules will produce
equivalent results.
G. Exponents
Objective 1.01.06
1. An exponent is a small number placed to the right and a little
above another number, called the base, to show how many times
the base is to be multiplied by itself. Thus, 34 (read "three to the
fourth power") means 3 used as a factor four times or 3 × 3 × 3 ×
3. In this case, 4 is the exponent, and 3 is the base.
2. In general, if b is any real number and n is any positive integer,
the nth power of b is written bn (where b is the base and n is the
exponent) and is read as "b to the nth power." This tells you that b
is used as a factor n times.
3. Thus, 52 is called "5 raised to the second power" (or 5 "squared"),
and 23 is called "2 raised to the third power" (or 2 "cubed").
When no exponent is shown for a number or no power is
indicated, the exponent or power is understood to be 1.
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Thus, 7 is the same as 71. Any number raised to the power of zero
equals one; e.g., 70 = 1. Normally, exponents of zero and one are
not left as the final value, but are changed to the simpler form of
the base.
4. Exponents can be expressed as integers, as in the examples above,
or as fractions or decimals such as 91/2 or 103.2 . They may also be
positive or negative.
5. Exponents and powers are particularly useful in mathematics not
only because they shorten the writing of mathematical
expressions, but also because they simplify many mathematical
operations. However, there are several special rules which govern
mathematical operations involving numbers with exponents.
6. Addition and Subtraction
a. The addition or subtraction of numbers with exponents can be
performed only if both the bases and the exponents of the
numbers are the same. When the bases of the exponents are
different, the multiplication indicated by the exponent must be
performed and the numbers then added or subtracted. Thus,
25 and 24 cannot be added directly because their exponents are
different. They can be added only by carrying out the
indicated multiplication first. Thus, 25 equals 2 × 2 × 2 × 2 ×
2 which equals 32, and 24 equals 2 × 2 × 2 × 2 which equals
16. Therefore, 25 + 24 equals 32 + 16, which equals 48.
b. When the bases and the exponents are the same, the numbers
can be added or subtracted directly. For example:
35 + 35 = 2(35) = 2(243) = 486
7. Multiplication
a. The multiplication of numbers with exponents of the same
base is performed by adding the exponents. The general form
is as follows:
(am)(an) = a(m+n)
b. It is important to remember that the bases of the numbers
must be the same before they can be multiplied by adding
their exponents. The base of the product is the same as the
base of the two factors. Thus,
32 × 33 = 3(2+3) = 35 = 243
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Section 8
Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
8. Division
a. The division of numbers with exponents of the same base is
performed by subtracting the exponent of the divisor
(denominator) from the exponent of the dividend (numerator).
The general form is:
−am
= a(m n)
an
b. Again, it is important to remember that the bases of the
numbers must be the same before they can be divided by
subtracting their exponents. The base of the quotient is the
same as the base of the number divided. Thus,
52 (5 2) 3
2 = 2 − = 2 = 8
2
c. Division of numbers with exponents can be used to show why
any number raised to the power of zero equals one. We know
that any fraction in which the numerator equals the
denominator can be reduced to 1; e.g., 2/2 = 1. Similarly:
32 (3 3) 0
3 = 2 − = 2 = 1
2
9. Exponent Raised to a Power
a. Raising a number with an exponent to a power is performed
by multiplying the exponent by the power. The general form
is:
(am)n = amn
b. The base of the answer is the same as the base of the number
raised to the power. Thus:
(52)3 = 5(2×3) = 56 = 15,625
10. Product Raised to a Power
a. Raising a product of several numbers to a power is performed
by raising each number to the power. The general form is as
follows:
nbn(ab)n = a
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b. Example:
[(2)(3)(4)]2 = (22)(32)(42) = (4)(9)(16) = 576
c. This same result can also be obtained like this:
[(2)(3)(4)]2 = 242 = 576
11. Mixed Product and Exponents Raised to a Power
a. The same rule can be used to raise a product of several
numbers with exponents to a power. The general form looks
like this:
(AaBbCc)n = A(a×n)B(b×n)C(c×n)
b. Example:
[(2)4(3)3(4)2]2 = (24×2)(33×2)(42×2) =(28)(36)(44) = (256)(729)(256)
12. Fraction Raised to a Power
a. Raising a fraction to a power is performed by raising both
numerator and denominator to the power. It should be
remembered that with a proper fraction (i.e., numerator is less
than the denominator) the resulting number must be less than
one. Also, the resulting number will be less than the value of
the original fraction. Thus, (2/3)3 equals 23/33, which equals
8/27, which is less than one and less than the original fraction,
2/3.
13. Negative Exponents and Powers
a. A negative exponent or power has a special meaning. Any
number, except 0, with a negative exponent equals the
reciprocal of the same number with the same positive
exponent. For example:
−2 1 16 = =
62 36
b. The same rules for addition, subtraction, multiplication,
division, and raising to a power apply to negative exponents
that apply to positive exponents. However, in adding,
subtracting, or multiplying the exponents, the rules for signed
numbers must also be observed.
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14. Fractional Exponents
a. Fractional exponents are used to represent roots (see next
m
section). The general form of a fractional exponent is a n ,
which reads "the nth root of am." For example, a½, means the
square root of a1, or a. In other words, a½ = a .
15. Calculator Method
a. To raise a number to a power using a scientific calculator, use
the following steps:
1) Enter the number. (Fractions must first be converted to
decimal form.)
yx2) Press the key.
3) Enter the power. (Fractions must first be converted to
decimal form.)
Section 9
4) Press the = key. The number displayed will be the
number entered in step 1 raised to the power entered
in step 3.
H. Square Roots
1. To square a number means to multiply the number by itself, i.e.,
raise it to the second power. (Consider that a square is two-
dimensional.) For example, 2 squared is 4, since 2 × 2 = 4. The
square of 3 is 9, 4 squared is 16, and so on.
2. Just as subtraction "undoes" addition and division "undoes"
multiplication, squaring a number can be "undone" by finding the
square root. The general definition is as follows:
If a2 = b, then a is a square root of b.
3. Be careful not to confuse the terms square and square root. For
example, if 52 = 25, this indicates that 25 is the square of 5, and 5
is the square root of 25. To be explicit, we say that it is a perfect
square because 5 times itself is 25.
4. All perfect squares other than 0 have two square roots, one
positive and one negative. For example, because 72 = 49 and
(-7)2 = 49, both 7 and -7 are square roots of 49. The symbol √,
referred to as the radical, is used to write the principal, or positive,
square root of a positive number.
Objective 1.01.07
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49 = 7 is read "The positive square root of 49 equals 7."
5. A negative square root is designated by the symbol − .
49− = −7 is read "The negative square root of 49 equals -7."
6. It is often convenient to use plus-or-minus notation:
means the positive or negative square root of 49.
7. Therefore, the rule is that every positive real number a has two
49±
square roots: a and − a .
8. It follows from the definition of square root that ( a )2
= a ,and
that a2 = a . Because the square of every real number is either
positive or zero, negative numbers do not have square roots in the
set of real numbers.
9. Notice that ⋅ =4 25 100 =10 , and 4 ⋅ 25 2 5 .= ⋅ = 10
Therefore, in general, we can say:
a. For any non-negative real numbers a and b:
a b a b⋅ = ⋅
a a
b. It also follows that =
b b
10. Calculator Method
a. To calculate the square root of any number using a scientific
calculator, follow these steps:
1) Enter the number. (Fractions must first be converted to
decimal form.)
2) Press the key. The number displayed will be the x
square root of the number entered in step 1. An
yxalternate method is to press the key and then
type 0.5. This raises the number in step 1 to the
power of 0.5, or ½.
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11. Other roots
a. For informational purposes only, we mention the fact that
other roots may be found for a number. One of these is the
cube root. To cube a number means to multiply the number
by itself three times, i.e., raise it to the third power. (Consider
that a cube is three-dimensional.) For example, 2 cubed is 8,
since 2 × 2 × 2 = 8. The cube root (or third root) of a number,
then, is the number that, when raised to the third power
(cubed), equals the first number. The notation for a cube root
is 3 a .
b. Note that any root may be taken from a number to "undo" an
exponent, such as the fourth or fifth root. The general
definition for a root is:
If an = b, then a is the nth root of b.
c. The notation for the nth root is n a . These roots follow the
same general rules as the square root.
I. Scientific Notation Objective 1.01.08
Section 10
1. The difficulty in writing very large or very small numbers in the
usual manner is that a large number of zeros are required to write
these numbers. This difficulty is overcome by using scientific
notation, in which integral powers of ten are used instead of a
large number of zeros to indicate the position of the decimal point.
In addition to simplifying the writing of very large or very small
numbers, scientific notation clearly identifies the number of
significant digits in a number and simplifies arithmetic
calculations involving multiplication, division, or raising to a
power. For these reasons, it is good practice to write numbers in
scientific notation when these operations are involved.
2. Converting From Standard Form To Scientific Notation
There are two steps involved in writing a number in scientific
notation.
a.
b.
Move the decimal point just to the right of the first significant
digit. The first significant digit is the first non-zero digit
counting from the left.
Indicate multiplication of the resulting number by a power of
ten that makes its value equal to the original value. The
power of ten is found by counting the number of places the
decimal point was moved from its original position. If
counted to the left, the power is positive; if counted to the
right, it is negative. For example:
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1) Suppose you want to express a number such as 700 in
scientific notation.
2700 7 10 ss = ×
2) Suppose you want to express 0.0014 in scientific notation.
30.0014 1.4 10−= ×rrr
3. Converting from Scientific Notation to Standard Form
a. To transform from scientific notation to standard form, follow
the opposite procedure.
51.96 10 1.96000 196,000 × = rrrrr =
22.27 10 002.27 0.0227× − = = ss
b. There are two parts of a number written in scientific notation,
the significant digits and the power of ten. Thus, in the
number 3.21 × 106, 3, 2, and 1 are the significant digits and
106 is the power of ten.
c. The ability to clearly see the number of significant digits can
be helpful in performing arithmetic calculations. For
example, the number of significant digits which should be
reported in the product of two numbers can be readily
determined if the two numbers are first written in scientific
notation.
d. When numbers are expressed in scientific notation,
calculations can be more easily visualized. This is because
they involve only numbers between 1 and 10 and positive and
negative integral powers of ten which can be treated
separately in the calculations using the rules for numbers with
exponents.
4. Addition and Subtraction Using Scientific Notation Objective 1.01.09
a. Addition and subtraction cannot normally be performed
directly using scientific notation because they require adding
or subtracting digits of equal place value. Thus, when
numbers expressed in scientific notation are to be added or
subtracted, they must first be converted to forms having equal
place value. This is commonly done by expressing them as
numbers which are multiplied by the same integral power of
ten.
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The sum or difference of these significant digits, multiplied
by their common power of ten, is the sum or difference of the
original numbers.
b. For example:
(3.54 × 105) + (2.51 × 104)
3.54 × 105 is first changed to 35.4 × 104
35.4×10 4
Section 11
+35.4×10 4
37.91 104 = ×105× 3.79
5. Multiplication and Division Using Scientific Notation
a. Multiplication or division of numbers using scientific notation
is performed by multiplying or dividing the significant digits
and the powers of ten separately. The significant digits are
multiplied or divided in the same manner as other mixed
decimals. The powers of ten are multiplied or divided by
adding or subtracting their exponents using the rules for
multiplication and division of numbers with exponents. For
example:
(2.7 × 102)(3.1 × 10-3) = (2.7)(3.1) × (102)(10-3) = 8.37 × 10-1
which should be rounded off to 8.4 × 10-1.
b. One of the most useful applications of scientific notation is in
arithmetic calculations which involve a series of
multiplications and divisions. The use of scientific notation
permits accurate location of the decimal point in the final
answer.
c. Example: Perform the following calculation using scientific
notation:
(219)( 0.00204)
(21.2)( 0.0312 )
1) Write each term in scientific notation:
2 −3(2.19×10 )( 2.04×10 )
1 −2(2.12×10 )( 3.12×10 )
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2) Multiply and divide the significant digits:
( )( )
( )( )
2.19 2.04 4.46 0.675
2.12 3.12 6.61
= =
3) Multiply and divide the powers of ten by adding and
subtracting exponents:
( )( )
( )( )
2 3 1
1 1 0
11 2
10 10 10 10 10
1010 10
− −
− +
−−
= = =
4) Combine the results:
0.675 × 100 = 0.675 = 6.75 × 10-1
6. "E" Notation
a. An alternate method for annotating scientific notation is often
used by pocket calculators, computers, and some references.
The method uses an E in place of the "× 10," and the number
written after the E is the exponent of 10. The standard and
alternate methods for scientific notation are equivalent and
can be converted from one form to another without a change
in value. The examples below use both methods in equivalent
expressions:
3.79 ×105 = 3.79E5
4.02 ×10-6 = 4.02E-6
5.89 ×100 = 5.89E0
7. Using "E" Notation with a Calculator
a. Numbers in scientific notation are entered into a scientific
calculator as follows:
1) Enter the significant digits.
2) Press the
vary.)
E or EXP key. (Actual key label may
3) Enter the power of 10. If the power is negative press the
+/! key in conjunction with entering the power.
J. Order of Mathematical Operations Objective 1.01.010
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1. In solving any equation it is necessary to perform the operations in
the equation in accordance with a certain hierarchy or order of
operations. Equations are solved by simplifying operations of
higher order first, according to group, left to right. The order for
solving equations is as follows:
a. Simplify expressions within grouping symbols, beginning
with the innermost set if more than one set is used.
b. Simplify all powers.
c. Perform all multiplications and divisions in order from left to
right.
d. Perform all additions and subtractions in order from left to
right.
2. For example:
(3 + 1)2 × 3 ! 14 ÷ 2
a. Simplify parentheses.
( )3 1 2 3 2+ 14 × − ÷
{
b. Simplify powers.
( )4 2 3 14 2× − ÷
{
c. Perform multiplication and division left to right.
16 3 14 2× − ÷ { {
d. Perform subtraction.
48 − =7 41 (Final Answer)
K. Algebra Objective 1.01.011
1. Algebra is the branch of mathematics which deals with the
Section 12
manipulation of words and letters, generically called symbols,
which represent numbers. Two factors contribute to the
widespread use of algebra in scientific calculations. First, by
using words and letters to represent the values of physical
quantities, physical relationships can be expressed in clear,
concise, and completely generalized form.
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Second, by using words and letters in place of numbers,
combinations of physical relationships may be simplified to yield
results applicable to any set of numbers.
2. For example, the area of a rectangle equals the product of the
length of the rectangle multiplied by its width. In generalized
terms, this statement can be written as:
Area = Length × Width
3. This expression is a simple rule which tells the relationship
between the area and the length and width of a rectangle. It does
not mean that words are multiplied together but rather that
numbers are inserted for the length and the width to obtain the
area. For example, if the length is 4 feet and the width is 2 feet,
the area is 2 feet × 4 feet or 8 square feet. This expression can be
further simplified by using symbols or letters instead of words.
For example, if area is designated by the letter A, length
designated by the letter l, and width designated by the letter w, the
following expression results:
A = l × w or A = lw
4. In algebraic expressions, when two or more letters representing
numbers are written next to each other without a symbol between
them, multiplication is indicated.
5. Variables vs. Numbers
When words or letters are used to represent numbers, they are
called variables. Thus, when letters like x, y, z, f, or k are used to
represent the values of physical quantities, they are called
variables because their value varies with the actual numbers they
may be chosen to represent. In the area calculation above, A, l,
and w are variables used to represent the numerical values of area,
length and width, respectively.
6. Properties of Variables
a. Recall that every number has a sign and an exponent
associated with it. Recall also that any number can be written
as a fraction by putting that number as the numerator and 1 as
the denominator, e.g., 5 = 5/1. These properties also apply to
any symbols that we might use to represent numbers.
Additionally, a symbol by itself stands for one of whatever
the variable represents. That is to say, the symbol a by itself
means "one of the variable represented by the letter a", or 1a.
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Combining this with the other "invisible" properties
mentioned, the symbol a is understood to represent "positive
one of the variable represented by the letter a to the power of
one, over 1," which would be expressed as:
1 1+ a
= a
1
b. An expression that is either a numeral, a variable or the
product of a numeral and one or more variables is called a
monomial. A combination or sum of monomials is called a
polynomial. Examples of each are:
1) Monomials
12 z 2 3 r −4x3
2) Polynomials
3x + 9 6a2 - 15
7. Equations
a. An equation is a statement that indicates how two quantities
or expressions are equal. The two quantities are written with
an equal sign (=) between them. For example,
1 + 1 = 2 10 = 6 - (-4)
5 × 3 = 15 18 ÷ 2 = 9
Section 13
are all equations because in each case the quantity on the left
side is equal to the quantity on the right side.
b. In algebra we use variables to represent numbers in equations.
In this lesson we will manipulate and solve equations
involving more than one variable, but we will find the
solution, i.e., the final answer, to equations having only one
variable.
8. Algebraic Manipulation
a. The basic principle, or axiom, used in solving any equation is:
whatever operation is performed on one side of an equation,
be it addition, subtraction, multiplication, division, raising to
an exponent, taking a root, must also be performed on the
other side if the equation is to remain true. This principle
must be adhered to in solving all types of equations.
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b. This axiom can be thought of by visualizing the balancing of
a scale. If the scale is initially balanced, it will remain
balanced if the same weight is added to both sides, if the same
weight is removed from both sides, if the weights on both
sides are increased by the same factor, or if the weights on
both sides are decreased by the same factor.
c. Here are the general forms for algebraic manipulation of
equations. For the real numbers a, b, c and n:
See Table 2. - "Rules for
Algebraic Manipulation"
1) Addition
If a = b, then a + c = b + c
2) Subtraction
If a = b, then a - c = b - c
3) Multiplication
If a = b, then a x c = b x c
4) Division
If a = b, then a ÷ c = b ÷ c
5) Involution
If a = b, then an = bn
Involution - raising to an
exponent.
6) Evolution Evolution - taking a root.
If a = b, then n a = n b
9. Manipulating and Solving Linear Equations
a. The addition or subtraction of the same quantity from both
sides of an equation may be accomplished by transposing a
quantity from one side of the equation to the other.
Transposing is a shortened way of applying the addition or
subtraction axioms. Any term may be transposed or
transferred from one side of an equation to the other if its sign
is changed. Thus, in the equation below the +4 can be
transposed to the other side of the equation by changing its
sign:
5x + 4 = 14
(5x + 4) - 4 = (14) - 4
5x = 14 - 4
5x = 10
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b.
c.
Transposing also works with multiplication and division.
Remembering that any number can be expressed as a fraction
we can rewrite the last line of the equation above. We can
then move the 5 in the numerator of the left side to the
denominator of the right side:
5x 10
=
1 1
x 10
=
1 5
10 x =
5
x = 2
Some linear equations may contain multiple terms
(monomials) involving the same variable. In order to
simplify the equation like terms must be combined. Don't
forget those "invisible properties of variables." Here's an
example:
Solve for x in the equation:
3x - 5 = x + 3
1) Subtract x from both sides:
3x - 5 - x = x + 3 - x
2) Combine like terms and cancel:
2x - 5 = 3
3) Add 5 to both sides:
2x - 5 + 5 = 3 + 5
4) -5 and +5 cancel:
2x = 8
5) Divide both sides by 2:
2x 8
=
2 2
6) 2 over 2 cancels. Reduce.
x = 4
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10. Quadratic Equations
Section 14
a. In manipulating an equation involving multiple variables, the
"variable of interest" (or the variable to be solved for) must be
moved to one side of the equal sign and all other variables
must be moved to the other side. In order to accomplish this,
operations must be performed on both sides of the equation
that will result in a variable, or group of variables, to be
canceled out from one side. This cancellation can only occur
if the "opposite function" is performed on a function that
already exists on that side of the equation. This means that a
variable that is being multiplied can be canceled by dividing
by the same variable. Addition can be canceled with
subtraction, multiplication with division, etc.
b. Example:
Solve for a in the equation:
a + b = c
1) Subtract b from both sides:
a + b - b = c - b
2) +b and -b cancels, leaving:
a = c - b
c. Example:
Solve for a in the equation:
ab = c
1) Divide both sides by b:
ab c
=
b b
2) b over b cancels, leaving:
c
a =
b
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d.
e.
Do not forget that the order of operations must be observed
when manipulating equations. Otherwise a completely
different solution may result. The key is to do the opposite
function in reverse order. Here is an example which shows
how this is done.
Solve for a in the equation:
a b+
= d
c
1) Multiply both sides by c:
(a b)+
c ⋅ = d ⋅c
c
2) c over c cancels:
a b dc + =
3) Subtract b from both sides:
a b b b+ − = dc −
4) b - b cancels, leaving:
a dc −b=
Once the order of the arithmetic functions has been
established, manipulation of the formula can begin. In the
example above, if the values for a, b, and c were known, the
first step would be to add b to a. The second step would be to
divide by c. Therefore, in order to solve it, we do the
opposite functions in reverse order. So, we first multiply by
c. Then, we would subtract b. It is a good idea to rewrite the
equation each time so that the operations can be reevaluated
before the next step. One final example:
Solve for d in the equation:
ab2 = cd 2
1) Divide both sides by c:
ab2 cd 2
=
c c
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2) c over c cancels:
ab2
2= d
c
3) Take the square root of both sides:
2
2ab d
c
=
4) Square root of square cancels, leaving:
ab2
= d
c
11. Substitution
Linear equations are solved by combining like terms and reducing
to find the solution. Quadratic equations are solved by
substituting given values into the equation for all but one of the
variables, thus making it a linear equation. The best approach is
to first solve for the variable of interest by algebraic manipulation.
Then find the solution by substituting the given values into the
equation for the respective variables. The single, unknown
variable, or the variable of interest, will be left on one side, being
set equal to the solution. For example:
Given the equation:
2x - y2 = 3a - b
Where x = 5, y = (-4) and a = 3; solve for b
a. To solve for b:
2x - y2 = 3a - b
b. Add b to both sides:
2x - y2 + b = 3a - b + b
c. b + b cancels:
2x - y2 + b = 3a
d. Transpose 2x - y2 to right side:
b = 3a - 2x + y2
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e. Substitute known values:
b = 3(3) - 2(5) + (-4)2
f. Perform operations:
b = 9 - 10 + 16
g. Simplify:
Section 15
b = 15
Objective 1.01.012
L. Logarithms
1. In many cases, arithmetic operations can be performed much more
quickly if the numbers involved are numbers with exponents to
the same base. For example, the multiplication or division of
numbers with exponents to the same base can be performed by
merely adding or subtracting the exponents. Raising to a power or
taking a root can be performed by merely multiplying or dividing
the exponents by the power or root. It is this feature of numbers
with exponents which led to the development of logarithms. If all
numbers could be readily written as numbers with exponents to
the same base, multiplication, division, raising to powers and
taking roots could be performed much more quickly.
2. Any number can be expressed as a power of any other number.
For example, 64 equals 26, 43, or 82. 64 also equals 72.137 or
101.806 . The use of logarithms involves expressing numbers as
powers of a common number, such as 10, so that arithmetic
operations with these numbers can be performed more quickly.
3. Simply put, a logarithm is an exponent. More explicitly, the
logarithm of a number (n) is the exponent (x) of a given base (B)
that is required to produce that number. The symbol log is used to
denote taking a logarithm. The base is usually indicated by a
small number written to the right and slightly below the symbol
log. The general relationship and form are as follows:
If n = Bx;
where B > 0 and B ≠ 1;
then: logBn = x
4. For example:
1000 = 103 → log101000 = 3
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5.
6.
7.
8.
9.
This says that the base ten logarithm of 1000 is 3, which means
that the base number, 10, must be raised to the power of 3 to equal
1000.
Here are some additional examples:
23 = 8 → log2 8 = 3
43/2 = 8 → log4 8 = 3/2
Before the development of the pocket calculator, the use of
logarithms saved considerable computation time. For example,
the evaluation of the following expression by hand would take a
very long time.
895 3 0.0247 2 93,800
(0.00186)( 4.53)2
( ) ( )
1
( )
However, using logarithms the above expression could be
evaluated in a matter of minutes. Thus, logarithms, or logs,
became one of the most useful tools in mathematics. In addition
to simplifying arithmetic calculations and shortening computation
time, logs are also important in engineering applications. The
relationship between a number and its logarithm is used frequently
to assist in measuring physical quantities when they vary over a
wide range. For example, logarithmic scales are used to measure
the neutron flux in nuclear reactors. Logarithms are also used for
scales on charts and meters.
Properties of Logarithms
a. Since logarithms are exponents, the basic rules of exponents
can be used to develop several useful properties of
logarithms. Suppose that a, x, and y are numbers, and a is a
suitable base for a logarithm (a > 0, a ≠ 1). The product rule
for exponents says:
y (x + y) ax ≅ a = a
b. Let us say that:
u = ax and v = ay
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c. If we write each of these in logarithmic form we would have:
x = loga u and
y = loga v
d. Then: u · v = ax · ay = a(x + y)
e. If we write this in logarithmic form it would be:
loga (u · v) = x + y
f. If we substitute the values for x and y from above we have:
g.
loga (u · v) = loga u + loga v
Section 16
This results in one of the rules for logarithms, the product
rule. Using similar methods, we could also prove the other
two rules that have been developed for logarithms.
See Table 3 - "Rules
for Logarithms"
10. Base Ten Logarithms
a.
b.
c.
Logs with the base of 10 are the most commonly used
logarithms because of their relationship to the place values in
the decimal system. Because of their wide use, base ten
logarithms are often referred to as common logarithms.
Observe the patterns in the number line and table. Notice the
relationship between the power of ten and the logarithm.
Any number can be expressed as a power of ten. Thus, 10
equals 101, 1,000 equals 103, 64 equals 101.806 and 527.3
equals 102.722 . Once a number has been expressed as a power
of ten, the base ten logarithm of the number is known it is the
exponent of 10. Thus log10 10 equals 1, log10 1000 equals 3,
log10 64 equals 1.806 and log10 527.3 equals 2.722. Since
base ten logarithms are so commonly used, the subscript 10 is
often omitted after the symbol log. Thus, log 27.3 means the
logarithm of 27.3 to the base 10.
Refer students to number
of line showing powers
of 10 and Table 4 - "Log
to Power of 10
Relationship."
d. A common logarithm is most often a mixed number
consisting of a whole number part and a decimal fraction part.
The whole number part is called the characteristic of the
logarithm. The decimal fraction part is called the mantissa.
For example, in the logarithm of 527.3, which equals 2.722,
the characteristic is 2 and the mantissa is 0.722. The
mantissas of most logarithms are rounded off to a specified
number of significant digits. Typically, mantissas are
rounded off to three, four, five or more significant digits.
1.01 - 34
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Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
11. Log-Table Method
a. To find the common logarithm of a number using four-place
log tables, use the following steps:
See Table 5 - "Four
place Logarithms"
1) Write the number in scientific notation with up to four
significant digits.
2) Using the product rule for logarithms, write the log of the
product as the sum of the logs of the factors.
3) Determine the mantissa as follows:
a) Find the row in the table corresponding to the first two
digits of the number, then move over to the column
corresponding to the third digit of the number.
b) Find the number under the proportional parts section
corresponding to the fourth digit of the number, and
add it to the last digit of the decimal obtained in step
3.a.
4) Determine the characteristic by using the power of 10
written in step 1 and write the logs in the form of a sum.
NOTE: If the power of 10 is negative, the log may be left
in this form.
NOTE: If the power of 10 is negative, the mantissa will
be changed because of the subtraction of a whole
number.
Do examples in the
study guide.
b. As you may have observed, the mantissa of the base ten
logarithm of a number depends only on the succession of
significant digits in the number. The position of the decimal
point in the number does not affect the mantissa. Of course,
the characteristics are different for each of these numbers.
See Table 6 - "Mantissa
for Successive
Significant Digits."
c. Note that any time the logarithm of a number is rounded off it
would be considered an approximate answer since each digit
is necessary to exactly duplicate the number when the base is
raised to that exponent. Since each significant digit of the
logarithm affects the actual value of the number, a standard of
four significant digits should maintained to ensure appropriate
accuracy in the answers.
Section 17
12. Calculator Method
1.01 - 35
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Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
Since hand-held scientific calculators are readily available today,
it is impractical to use log tables. To find the logarithm of a
number with a calculator:
a. Enter the number.
b. Press the log key. The number displayed is the
logarithm of the number entered in step 1.
13. Natural Logarithms
a. A logarithm can be written to any base. For most practical
computations, base ten logarithms are used because of their
relationship to the place values in the decimal system.
However, in many scientific and engineering problems, it is
convenient to use another base, symbolized by the letter e. e
is an irrational number whose value is 2.71828 . . . The actual
value of e is the limiting value of (1 + 1/n)n as n gets larger
and larger.
b. Although it is an irrational number, it can still be used as the
base for logarithms in the same way as 10 is used for base ten
logarithms. e is the basis for many laws of nature, such as the
laws of growth and decay of physical quantities, including the
decay of radioactive substances and the growth and decay of
neutron population in a nuclear reactor. Because of the
relationship of e to natural phenomena, logarithms to the base
e are called natural logarithms.
c. The natural logarithm of a number is the exponent to which e
must be raised in order to get that number. The symbol ln is
used to denote a natural logarithm which is the same as saying
loge. The relationship is expressed as follows:
If ex = n then ln n = x
d. For example:
1) ln 2 = 0.693147
0.693147... = 2. which means that e
2) ln 10 = 2.302585
2.302585... = 10. which means that e
3) ln e = 1
which means that e1 = e
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Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
e. Natural logarithms are not often used for computations.
However, they appear frequently in decay and shielding
calculations problems because of the relationship of e to
natural phenomena. As a result, it is important to know how
to determine the natural logarithms of numbers.
f. Tables of natural logarithms are available in several standard
handbooks. However, there are several important differences
between natural logarithms and base ten logarithms which
must be understood to use natural logarithms. A natural
logarithm is not separated into a characteristic and a mantissa.
This is because the whole number part of a natural logarithm
does not relate to the position of the decimal point.
Therefore, tables of natural logarithms give the entire
logarithm, not just the decimal fraction part. Moreover, if a
natural logarithm is negative, the entire logarithm is negative
and is shown as such in a table of natural logarithms. Further,
there is no part of the natural logarithm of a number which is
not affected by the position of the decimal point. For all these
reasons, tables of natural logarithms cannot be made concise.
g. To find the natural log of a number using a hand-held
calculator:
1) Enter the number.
2) Press the ln key. The number displayed is the
natural logarithm of the number entered in step 1.
14. Antilogarithms
Section 18
a. An antilogarithm, usually shortened to "antilog," is the
opposite of a logarithm and is much easier to do. The antilog
of a given number is the value obtained by raising the base to
that number. Finding antilogs is an important part in the
overall use of logarithms in computations. If numbers are
converted to logarithms to perform calculations, the answer
must be converted back from logarithms once the calculations
have been performed. The symbol log-1 is used in
calculations to indicate the antilog is going to be taken. The
base of 10 is assumed unless otherwise noted. The general
form is:
log-1 x = n which means 10x = n
b. For example:
log-1 3 which means 103 = 1000 Refer also to example in
study guide.
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Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
c. On a scientific calculator the base 10 antilog of a number is
obtained by raising the base (10) to that number.
1) Enter the number.
See Table 7 -log−1 or 10x key. The number 2) Press the
"Summary of Log
displayed is the antilog of the number of entered in Definitions."
step 1. In other words, 10 raised to that power.
d. The symbol ln-1 is used to denote the inverse natural log, i.e.
the antilog of base e.
ln-1 x = n which means ex = n
e. For example:
0.693... = 2
ln-1 0.693 which means e
f. On a scientific calculator the inverse natural log of a number
is obtained as follows:
1) Enter the number.
ex2) Press the Ln-1 or key. The number displayed is
the inverse natural log of the number of entered in
step 1. In other words, e raised to that power.
14. Solving for Variables as Exponents
a. One of the useful applications for logarithms is to solve
algebraic equations with unknown exponents. In the
following example, for instance, if the exponent is not known,
it would be difficult to determine the correct value of x in
order to make the statement (or equation) true.
2356 = 3x
b. With the use of logarithms, however, this type of problem can
be easily solved. The steps for solving an equation of this
type are:
1) Make sure the base raised to the unknown exponent is
isolated on one side of the equation (this may involve
some manipulation of the formula in more complicated
equations).
2) Take the log of both sides of the equation:
log 2356 = log 3x
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Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
3) Since a logarithm is an exponent, and this is an exponent
raised to a power, this statement can now be rewritten
using the laws of exponents, which say that the exponent
and power are multiplied:
log 2356 = (log 3)(x)
4) Divide both sides by log 3 which moves it to the right side
of the equation:
log 2356 (log 3 )( x)
=
log 3 log 3
5) Cancel terms and rewrite the equation:
log 2356
= x
log 3
6) Perform the operations and solve:
3.372
= x
0.477
7.068 = x
c. This answer can now be checked by substituting it back into
the original equation to see if it makes the statement true:
2356 = 37.068
d. Some problems may involve the base of the natural logarithm,
e, raised to an unknown power. This exponent can be
determined by isolating e on one side of the equation and then
taking the natural log of both sides. This is done because
taking the natural log of e reduces to 1. For example:
n125 = 1000e
125 n= e
1000
125 nln = ln e
1000
ln 0.125 = (ln e)(n)
ln 0.125 = (1)(n)
-2.0794 = n
1.01 - 39
DOE-HDBK-1122-2009
Section 19
Module 1.01 Basic Mathematics and Algebra Instructor’s Guide
III. SUMMARY
A. Review major topics
1. Fractions
2. Decimals
3. Percent
4. Signed Numbers
5. Exponents
6. Square Roots
7. Scientific Notation
8. Order of Mathematical Operations
9. Algebra
10. Logarithms
B. Review learning objectives
IV. EVALUATION
Evaluation should consist of a written examination comprised of multiple
choice questions. 80% should be the minimum passing criteria for the
examination.
1.01 - 40
DOE-HDBK-1122-2009
Module 1.02 Unit Analysis and Conversion Instructor’s Guide
Course Title: Radiological Control Technician
Module Title: Unit Analysis & Conversion
Module Number: 1.02
Objectives:
1.02.01 Identify the commonly used unit systems of measurement and the base units for
mass, length, and time in each system.
1.02.02 Identify the values and abbreviations for SI prefixes.
1.02.03 Given a measurement and the appropriate conversion factor(s) or conversion
factor table, convert the measurement to the specified units.
1.02.04 Using the formula provided, convert a given temperature measurement to
specified units.
References:
1. "Health Physics and Radiological Health Handbook"; Shleien; 1992.
2. DOE-HDBK-1010-92 (June 1992) "Classical Physics" DOE Fundamental Handbook; US
Department of Energy.
3. "Chart of the Nuclides"; Sixteenth Edition, Knolls Atomic; 2003.
Instructional Aids:
1. Overheads
2. Overhead projector/screen
3. Chalkboard/whiteboard
4. Lessons Learned
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Module 1.02 Unit Analysis and Conversion Instructor’s Guide
I. MODULE INTRODUCTION
A. Self Introduction
1. Name
2. Phone number
3. Background
4. Emergency procedure review
B. Motivation
A knowledge of the unit analysis and conversion process is a necessity
for the RCT. It is useful for air and water sample activity calculations,
contamination calculations, and many other applications.
C. Overview of Lesson
1. Units
2. Unit systems
3. Unit analysis and conversions including use of conversion factor
tables
O.H.: Objectives
D. Introduce Objectives
II. LESSON OUTLINE
A. Units and Measurements
1. Units are used to express physical quantities or measurements, i.e.,
length, mass, etc. All measurements are actually relative in the
sense that they are comparisons with some standard unit of
measurement. Two items are necessary to express these physical
quantities:
a. A number--expresses the magnitude.
b. A unit--expresses the dimension.
2. A number and a unit must both be present to define a measurement.
3. Measurements are algebraic quantities and as such may be
mathematically manipulated subject to algebraic rules.
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Module 1.02 Unit Analysis and Conversion Instructor’s Guide
4. Fundamental Quantities
All measurements or physical quantities can be expressed in terms
of three fundamental quantities. They are called fundamental
quantities because they are dimensionally independent. They are:
See Fig. 1 in the
Study Guide -
"Fundamental
Units"
a. Length (L)
b. Mass (M) (not the same as weight)
c. Time (T)
5. Derived Quantities
Other quantities are derived from the fundamental quantities.
These derived quantities are formed by multiplication and/or
division of fundamental quantities. For example:
a. Area is the product of length times length (width), which is L ×
L, or L2.
b. Volume is area times length, which is length times length times
length, or L3.
Section 20
c. Velocity is expressed in length per unit time, or L/T.
d. Density is expressed in mass per unit volume, or M/L3.
B. Systems of Units Objective 1.02.01
1. The units by which physical quantities are measured are established
in accordance with an agreed standard. Measurements made are
thereby based on the original standard which the unit represents.
The various units that are established, then, form a system by which
all measurements can be made.
2. English System See Table 1 of the
Study Guide -
"English System
Base Units"
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Module 1.02 Unit Analysis and Conversion Instructor’s Guide
a. The system that has historically been used in the United States
is the English System, sometimes called the English
Engineering System (EES). Though no longer used in England,
many of the units in this system have been used for centuries
and were originally based on common objects or human body
parts, such as the foot or yard. Though practical then, the
standards for these units were variable as the standard varied
from object to object, or from person to person.
b. Even though fixed standards have since been established for
these antiquated units, no uniform correlation exists between
units established for the same quantity. For example, in
measuring relatively small lengths there are inches, feet, and
yards. There are twelve inches in a foot, and yet there are only
three feet in a yard. This lack of uniformity makes conversion
from one unit to another confusing as well as cumbersome.
However, in the U.S., this system is still the primary system
used in business and commerce.
3. International System of Units (SI)
a. Since the exchange of scientific information is world-wide
today, international committees have been set up to standardize
the names and symbols for physical quantities.
b. In 1960, the International System of Units (abbreviated SI from
the French name Le Système Internationale d'Unites) was
adopted by the 11th General Conference of Weights and
Measures (CGPM).
c. The SI, or modernized metric system, is based on the decimal
(base 10) numbering system. First devised in France around
the time of the French Revolution, the metric system has since
been refined and expanded so as to establish a practical system
of units of measurement suitable for adoption by all countries.
The SI system consists of a set of specifically defined units and
prefixes that serve as an internationally accepted system of
measurement. Nearly all countries in the world use metric or
SI units for business and commerce as well as for scientific
applications.
4. SI Prefixes
Objective 1.02.02
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Module 1.02 Unit Analysis and Conversion Instructor’s Guide
See Table 2 of the
a. The SI system is completely decimalized and uses prefixes for
the base units of meter (m) and gram (g), as well as for derived
units, such as the liter (l) which equals 1000 cm3.
Study Guide - "SI
Prefixes"
b. SI prefixes are used with units for various magnitudes
associated with the measurement being made. Units with a
prefix whose value is a positive power of ten are called
multiples. Units with a prefix whose value is a negative power
of ten are called submultiples.
Section 21
c. For example, try using a yard stick to measure the size of a
frame on film for a camera. Instead you would use inches,
because it is a more suitable unit. With the metric system, in
order to measure tiny lengths, such as film size, the prefix milli-
can be attached to the meter unit to make a millimeter, or
1/1000 of a meter. A millimeter is much smaller and is ideal in
this situation. On the other hand, we would use a prefix like
kilo- for measuring distances traveled in a car. A kilometer
would be more suited for these large distances than the meter.
See Table 3 in the
d. Prior to the adoption of the SI system, two groups of units were
commonly used for the quantities length, mass, and time: MKS
and CGS.
Study Guide -
"Metric
Subsystems"
5. SI Units
a. There are seven fundamental physical quantities in the SI
system. These are length, mass, time, temperature, electric
charge, luminous intensity, and molecular quantity (or amount
of substance). In the SI system there is only one SI unit for
each physical quantity. The SI system base units are those in
the metric MKS system. Table 4 in the Study Guide lists the
seven fundamental quantities and their associated SI unit. The
units for these seven fundamental quantities provide the base
from which the units for other physical quantities are derived.
See Table 4 in the
Study Guide -
"International
System (SI) Units"
b. For most applications the RCT will only be concerned with the
first four quantities as well as the quantities derived from them.
6. Radiological Units
In the SI system, there are derived units for quantities used for
radiological control. These are the becquerel, the gray,
1.02 - 5
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Module 1.02 Unit Analysis and Conversion Instructor’s Guide
and the sievert. The SI unit of activity is the becquerel, which is the
activity of a radionuclide decaying at the rate of one spontaneous
nuclear transition per second. The gray is the unit of absorbed
dose, which is the energy per unit mass imparted to matter by
ionizing radiation, with the units of one joule per kilogram. The
unit for equivalent dose is the sievert, which has units of joule per
kilogram. These quantities and their applications will be discussed
in detail in Lesson 1.06.
7. Other units
There are several other SI derived units that are not listed in Table 4
of the Study Guide. It should be noted that the SI system is
evolving and that there will be changes from time to time. The
standards for some fundamental units have changed in recent years
and may change again as technology improves our ability to
measure even more accurately.
C. Unit Analysis and Conversion Process
1. Units and the Rules of Algebra
a. Remember that a measurement consists of a number and a unit.
When working problems with measurements, it should be noted
that the measurement units are subject to the same algebraic
rules as the values. Some examples are provided below.
2(cm) × (cm ) = cm
3ft 2= ft
ft
1
= yr−1
yr
b. As a result, measurements can be multiplied, divided, etc., in
order to convert to a different system of units. Obviously, in
order to do this, the units must be the same. For example, a
square measures one foot in length and 18 inches in width. To
find the area of the square in square inches we must multiply
the length by the width. However, when the measurements are
in different units, and cannot be multiplied directly.
Objective 1.02.03
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Section 22
Module 1.02 Unit Analysis and Conversion Instructor’s Guide
c. We can convert feet to inches. We know that there are 12
inches in one foot. We can use this ratio to convert 1 foot to 12
inches. Then we can then calculate the area as 12 inches × 18
inches, which equals 216 in2, which is a valid measurement.
2. Steps for Unit Analysis and Conversion
a. Determine given units and desired units.
b. Build (or obtain) conversion factor(s) -- see Conversion Tables
at end of lesson.
1) A conversion factor is a ratio of two equivalent physical
quantities expressed in different units. When expressed as
a fraction, the value of all conversion factors is 1. Because
a conversion factor equals 1, it does not matter which value
is placed in the numerator or denominator of the fraction.
2) Examples of conversion factors are:
365 days
1year
12inches
1 foot
1foot3
2.832E4cm 3
3) Building conversion factors involving the metric prefixes
for the same unit can be tricky. This involves the
conversion of a base unit to, or from, a subunit or superunit.
4) To do this, use the following steps:
Example: 1 gram to milligrams
a) Place the base unit in the numerator and the subunit/
superunit in the denominator (or vice versa):
1.02 - 7
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Module 1.02 Unit Analysis and Conversion Instructor’s Guide
g
mg
b) Place a 1 in front of the subunit/superunit:
g
1mg
c) Place the value of the prefix on the subunit/ superunit
in front of the base unit:
m (milli-) = 10-3 or 1E-3
1E − 3g
1mg
5) Also remember that algebraic manipulation can be used
when working with metric prefixes and bases. For
example, 1 centimeter = 10-2 meters. This means that
1 meter = 1/10-2 centimeters, or 100 cm. Therefore, the two
conversion factors below are equal:
1E − 2m 1m
=
1cm 100cm
c. Set up an equation by multiplying the given units by the
conversion factor(s) to obtain desired unit(s).
1) When a measurement is multiplied by a conversion factor,
the unit(s) (and probably the magnitude) will change;
however, the actual measurement itself does not change.
For example, 1 ft and 12 inches are still the same length;
only different units are used to express the measurement.
2) By using a "ladder" or "train tracks," a series of
conversions can be accomplished in order to get to the
desired unit(s). By properly arranging the numerator and
denominator of the conversion factor(s), given and
intermediate units will cancel out by multiplication or
division, leaving the desired units. Some examples of the
unit analysis and conversion process follow:
1.02 - 8
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Module 1.02 Unit Analysis and Conversion Instructor’s Guide
3. Example 1: Convert 3 years to seconds.
Step 1 - Determine given and desired unit(s):
Given units: years
Desired units: seconds.
Step 2 - Build/obtain conversion factor(s):
We can use multiple conversion factors to accomplish this problem:
1 year = 365.25 days
1 day = 24 hours
1 hour = 60 minutes
1 minute = 60 seconds; 1 hour = 3600 seconds
Step 3 - Analyze and cancel given and intermediate units. Perform
multiplication and division of numbers:
⎜
⎛
⎜
⎝
3
years
⎟⎜
⎛
⎜
⎝
⎞
⎟
⎠
365.25days
year
⎛
⎜
⎝
⎞
⎟⎟⎜
⎠
24hours ⎛
⎜
⎝
⎞
⎟
⎠
⎟
3600sec⎞
⎟
⎠
=94,672,800sec
day hour
4. Example 2: What is the activity of a solution in
μ
Ci
if
ml
dpm
it has 2000 ?
gallon
Step 1 - Determine given and desired unit(s):
dpm
Given units:
gallon
Desired units:
μ
Ci
ml
1.02 - 9
DOE-HDBK-1122-2009
Section 23
Module 1.02 Unit Analysis and Conversion Instructor’s Guide
Step 2 - Build conversion factor(s):
1 liter = 0.26418 gallons
1 dpm = 4.5 E-07 µCi
1 liter = 1000 ml
Step 3 - Analyze and cancel given and intermediate units. Perform
multiplication and division of numbers.
⎛ 2000dpm ⎞⎛ 4.5E − 7μCi ⎞⎛ 0.26418gal ⎞⎛ 1l ⎞ μCi
= 2.38E − 7⎜ ⎟⎜ ⎟⎜ ⎟⎜ ⎟
⎝ gal ⎠⎝ 1dpm ⎠⎝ 1l ⎠⎝ 1,000 ml ⎠ ml
D. Temperature Measurements and Conversions
1. Temperature measurements are made to determine the amount of
heat flow in an environment. To measure temperature it is
necessary to establish relative scales of comparison. Three
temperature scales are in common use today. The general
temperature measurements we use on a day-to-day basis in the
United States are based on the Fahrenheit scale. In science, the
Celsius scale and the Kelvin scale are used.
2. The Fahrenheit scale, named for its developer, was devised in the
early 1700's. This scale was originally based on the temperatures
of human blood and salt-water, and later on the freezing and boiling
points of water. Today, the Fahrenheit scale is a secondary scale
defined with reference to the other two scientific scales. The
symbol °F is used to represent a degree on the Fahrenheit scale.
3. About thirty years after the Fahrenheit scale was developed, Anders
Celsius, a Swedish astronomer, suggested that it would be simpler
to use a temperature scale divided into one hundred degrees
between the freezing and boiling points of water. For many years
his scale was called the centigrade scale. In 1948 an international
conference of scientists re-named it the Celsius scale in honor of its
inventor. The Celsius degree, °C, was defined as 1/100 of the
temperature difference between the freezing point and boiling point
of water.
Objective 1.02.04
See Fig. 2 in the
Study Guide -
"Comparison of
Kelvin, Celsius and
Fahrenheit scales"
1.02 - 10
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Module 1.02 Unit Analysis and Conversion Instructor’s Guide
4. In the 19th century, an English scientist, Lord Kelvin, established a
more fundamental temperature scale that used the lowest possible
temperature as a reference point for the beginning of the scale. The
lowest possible temperature, sometimes called absolute zero, was
established as 0 K (zero Kelvin). This temperature is 273.15°C
below zero, or -273.15°C. Accordingly, the Kelvin degree, K, was
chosen to be the same as a Celsius degree so that there would be a
simple relationship between the two scales.
5. Note that the degree sign (°) is not used when stating a temperature
on the Kelvin scale. Temperature is stated simply as Kelvin (K).
The Kelvin was adopted by the 10th Conference of Weights and
Measures in 1954, and is the SI unit of thermodynamic temperature.
Note that the degree Celsius (°C) is the SI unit for expressing
Celsius temperature and temperature intervals. The temperature
interval one degree Celsius equals one kelvin exactly. Thus,
0°C = 273.15 K by definition.
6. To convert from one unit system to another, the following formulas
are used:
o
o ( F −32)
1) C =
1.8
or
⎛ ⎞o o 5C = ( F −32)⎜ ⎟9⎝ ⎠
2) F =1.8( )o oC + 32
or
o ⎛ ⎞9 oCF = ( ) + 32⎜ ⎟5⎝ ⎠
3) K = oC + 273.15
See Table 5 in the
Study Guide -
"Equations for
Temperature
Conversions"
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Module 1.02 Unit Analysis and Conversion Instructor’s Guide
7. Example 3: Convert 65° Fahrenheit to Celsius:
o(65 F − 32)oC =
1.8
33
oC =
1.8
oC = 18.3oC
III. SUMMARY
Section 24
A. Review major topics
1. Units
2. Unit systems
3. Unit analysis and conversions including use of conversion factor
tables
B. Review learning objectives
IV. EVALUATION
Evaluation should consist of a written examination comprised of multiple
choice questions. 80% should be the minimum passing criteria for the
examination.
1.02 - 12
DOE-HDBK-1122-2009
Module 1.03 Physical Sciences Instructor’s Guide
Course Title: Radiological Control Technician
Module Title: Physical Sciences
Module Number: 1.03
Objectives:
1.03.01 Define the following terms as they relate to physics:
a. Work
b. Force
c. Energy
1.03.02 Identify and describe four forms of energy.
1.03.03 State the Law of Conservation of Energy.
1.03.04 Distinguish between a solid, a liquid, and a gas in terms of shape and volume.
1.03.05 Identify the basic structure of the atom, including the characteristics of subatomic
particles.
1.03.06 Define the following terms:
a. Atomic number
b. Mass number
c. Atomic mass
d. Atomic weight
1.03.07 Identify what each symbol represents in the X notation.
1.03.08 State the mode of arrangement of the elements in the Periodic Table.
1.03.09 Identify periods and groups in the Periodic Table in terms of their layout.
1.03.10 Define the terms as they relate to atomic structure:
a. Valence shell
b. Valence electron
References:
1. "Chart of the Nuclides"; Sixteenth Edition, Knolls Atomic; 2003.
2. "Modern Physics"; Holt, Rinehart and Winston, Publishers; 1976.
3. "Chemistry: An Investigative Approach"; Houghton Mifflin Co., Boston; 1976.
4. "Chemical Principles with Qualitative Analysis"; Sixth ed.; Saunders College Pub.; 1986.
5. "Introduction to Chemistry" sixth ed., Dickson, T. R., John Wiley & Sons, Inc.; 1991.
6. "Matter"; Lapp, Ralph E., Life Science Library, Time Life Books; 1965.
7. "Physics"; Giancoli, Douglas C., second ed., Prentice Hall, Inc.; 1985.
8. DOE/HDBK-1015 "Chemistry: Volume 1 of 2"; DOE Fundamentals Handbook Series;
January 1993.
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Module 1.03 Physical Sciences Instructor’s Guide
Instructional Aids:
1. Overheads
2. Overhead projector/screen
3. Chalkboard/whiteboard
4. Chart of the Nuclides
5. Periodic Table of the Elements
6. Lessons Learned
I. MODULE INTRODUCTION
A. Self-Introduction
1. Name
2. Phone number
3. Background
4. Emergency procedure review
B. Motivation
It is important to a RCT that they have a basic understanding of physics
because they may work in an environments where materials can undergo
changes in state, resulting in changes in the work environment.
C. Overview of Lesson
1. Physics definitions
2. Law of Conservation of Energy
3. The Atom
4. Periodic Table
5. Valence Electrons
O.H.: Objectives
D. Introduce Objectives
II. MODULE OUTLINE
A. Work and Energy
Physics is the branch of science that describes the properties, changes,
and interactions of energy and matter. This unit will serve as a brief
introduction to some of the concepts of physics as they apply to the
situations that may be encountered by RCTs. A general definition of
matter is anything that has mass and occupies space. Energy can be
understood by relating it to another physical concept - work.
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1. Work and Force Objective 1.03.01
a. Work is defined in physics as a force acting through a distance.
b. A force is a push or a pull. A more technical definition of force is
Section 25
any action on an object that causes the object to change speed or
direction.
c. Units
(1) Force is derived as the product of mass and acceleration.
(2) The SI derived unit is expressed in terms of newtons, (N)
Kg ×m
N = 2S
(3) Mathematically, work is expressed as:
W = F x d
where:
W = Work
F = Force (newtons)
d = Distance (meters)
(4) The SI unit of work is the joule
(5) One joule of work is performed when a force of one newton is
exerted through a distance of one meter.
(6) Thus:
J N m= ×
B. Energy Objective 1.03.02
1. Energy is defined as the ability to do work.
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a. Kinetic energy describes the energy of motion an object
possesses. For example, a moving airplane possesses kinetic
energy.
1 2E = mvK 2
Where:
m = mass
v = velocity
b. Potential energy indicates how much energy is stored as a result
of the position or the configuration of an object. For example,
water at the top of a waterfall possesses potential energy.
E = mghp
Where:
m = mass
g = free fall acceleration
h = vertical distance
c. Thermal energy describes the energy that results from the
random motion of molecules. For example, steam possesses heat
energy.
d. Chemical energy describes the energy that is derived from
atomic and molecular interactions in which new substances are
produced. For example, the substances in a dry cell provide
energy when they react.
2. Law of Conservation of Energy Objective 1.03.03
a. The Law of Conservation of Energy states that the total amount
of energy in a closed system remains unchanged. Stated in other
terms, as long as no energy enters or leaves the system, the
amount of energy in the system will always be the same,
although it can be converted from one form to another.
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b. Gasoline contains chemical energy that is released in the form of
heat when a chemical reaction (burning) with oxygen occurs.
This energy comes from the breaking and making of bonds
between atoms. New products, carbon dioxide and water, are
formed as the gasoline combines with oxygen. The energy of the
burning gasoline produces heat energy which causes the gaseous
combustion products to do work on the pistons in the engine.
The work results in the vehicle moving, giving it kinetic energy.
c. Units
(1) Thermal energy is often measured in units of calories (CGS)
or British Thermal Units or BTUs (English).
(a) A calorie is the amount of heat needed to raise the
temperature of 1 gram of water by 1 °C. One calorie is
equal to 4.18605 joules.
(b) A BTU is the amount of heat needed to raise the
temperature of 1 pound of water by 1 °F. One BTU is
equal to 1.055E3 joules.
(2) Electrical energy is sometimes expressed in units of
kilowatt-hours. One kw-hr is equal to 3.6E6 joules
(a) A very small unit used to describe the energy of atomic
and subatomic size particles is the electron volt (eV).
One electron volt is the amount of energy acquired by an
electron when it moves through a potential of one volt.
(b) It takes about 15.8 eV of energy to remove an electron
from an atom of argon.
(c) Superunits such as kiloelectron volt (keV) and
megaelectron volt (MeV) are used to indicate the
energies of various ionizing radiations.
d. Work-Energy Relationship
Section 26
(1) When work is done by a system or object, it expends energy.
For example, when gaseous combustion products push
against the pistons, the gas loses energy. The chemical
energy stored in the gasoline is used to do work so that the
car will move.
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Module 1.03 Physical Sciences Instructor’s Guide
(2) When work is done on a system or object, it acquires energy.
(3) The work done on the car by the combustion of the gasoline
causes the car to move, giving it more kinetic energy.
(4) When energy is converted to work or changed into another
form of energy, the total amount of energy remains constant.
Although it may appear that an energy loss has occurred, all
of the original energy can be accounted for.
(5) Consider the example of the automobile. The energy stored
in the gasoline is converted to heat energy, some of which is
eventually converted to kinetic energy. The remainder of the
heat energy is removed by the engine's cooling system. The
motion of the engine parts creates friction, heat energy,
which is also removed by the engine's cooling system. As
the car travels, it encounters resistance with the air. If no
acceleration occurs, the car will slow down and the kinetic
energy is converted to friction or heat energy. The contact of
the tires on the road converts some of the available kinetic
energy to heat energy (friction), slowing down the car. A
significant amount of the energy stored in the gasoline is
dissipated as wasted heat energy.
e. Energy-mass relationship
Energy can also be converted into mass and mass converted into
energy. This topic will be discussed further in Section 1.04
Nuclear Physics.
C. Energy and Change of State
1. Matter is anything that has mass and takes up space.
2. There are three states of matter solid, liquid and gas.
See Fig. 1 -
"Energy
Conversion in an
Automobile"
Objective 1.03.04
See Table 1 -
"State of Matter
Compared" and
Fig. 2 - "States of
Matter"
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3. Solid State
a. A solid has definite shape and volume. The solid state differs
from the liquid and gaseous states in that:
(1) The molecules or ions of a solid are held in place by strong
attractive forces.
(2) The molecules still have thermal energy, but the energy is
not sufficient to overcome the attractive forces.
(3) The molecules of a solid are arranged in an orderly, fixed
pattern.
4. Liquid State
(a) When heat is added to a substance, the molecules acquire more
energy, which causes them to break free of their fixed crystalline
arrangement. As a solid is heated, its temperature rises until the
change of state from solid to liquid occurs.
(b) The volume of a liquid is definite since the molecules are very
close to each other, with almost no space in between.
Consequently, liquids can undergo a negligible amount of
compression. However, the attractive forces between the
molecules are not strong enough to hold the liquid in a definite
shape. For this reason a liquid takes the shape of its container.
(c) High energy molecules near the surface of a liquid can overcome
the attractive forces of other molecules. These molecules
transfer from the liquid state to the gaseous state. If energy
(heat) is removed from the liquid, the kinetic energy of the
molecules decreases and the attractive forces can hold the
molecules in fixed positions. When compared with the kinetic
energy, the attractive forces are not strong enough to hold the
molecules in fixed positions, forming a solid.
Section 27
5. Gaseous State
(a) If the temperature of a liquid is increased sufficiently, it boils,
that is, molecules change to the gaseous state and escape from
the surface. Eventually, all of the liquid will become a gas.
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(b) A gas has both indefinite shape and indefinite volume. A large
space exists between gas molecules because of their high thermal
energy. This allows for even more compression of a substance
in the gaseous state.
D. The Atom Objective 1.03.05
1. The Bohr Model was described by Ernest Rutherford and Niels Bohr
– 1911
See Fig. 3 - Atomic
Model
a. Made of protons, neutrons, and electrons
b. Central core called the nucleus
c. Contains protons and neutrons
d. Nuclear forces hold nucleus together
2. Protons
a. Positively charged (+1)
b. Mass = 1.6726 x 10-24 gm or 1.007276470 amu
c. Each element is determined by the number of protons in its
nucleus. All atoms of the same element have the same number
of protons.
3. Neutrons
a. Neutrally charged (0)
b. Mass = 1.6749 x 10-24 gm or 1.008665012 amu
c. Determines the isotope of an element. Same number of protons
(therefore, of the same element) but different number of
neutrons. Does not affect chemical property of element.
4. Electrons
a. Negatively charged (-1)
b. Small mass = 9.1085 x 10-28 or 0.00054858026 amu (1/1840 of a
proton)
c. The mass of an electron is so small as compared to that of a
proton or neutron, virtually the entire mass of an atom is
furnished by the nucleus.
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d. Number of electrons is normally equal to the number of protons
(atom is electrically neutral)
e. The number of electrons in the outermost shell determines the
chemical behavior or properties of the atom.
E. The Elements
1. Even though all atoms have the same basic structure, not all atoms
are the same. There are over a hundred different types of atoms.
These different types of atoms are known as elements. The atoms of
a given element are alike but have different properties than the atoms
of other elements.
2. Elements are the simplest forms of matter. They can exist alone or
in various combinations. Different elements can chemically combine
to form molecules or molecular compounds. For example, water is a
compound, consisting of water molecules. These molecules can be
decomposed into the elements hydrogen and oxygen. The elements
hydrogen and oxygen are fundamental forms of matter. They cannot
be further separated into simpler chemicals.
3. Chemical Names See Table 2 - "List
of Elements by
a. Currently, there are more than 110 named elements. Some have Name"
been known for many centuries, while others have only been
discovered in the last 15 or 20 years. Each element has a unique
name. The names of the elements have a variety of origins.
Some elements were named for their color or other physical
characteristics. Others were named after persons, places, planets
or mythological figures.
b. For example, the name chromium comes from the Greek word
chroma, which means "color." Chromium is found naturally in
compounds used as pigments. The elements curium,
einsteinium, and fermium were named after famous nuclear
physicists. Germanium, polonium and americium, were named
after countries. Uranium, neptunium and plutonium are named
in sequence for the three celestial bodies Uranus, Neptune and
Section 28
Pluto.
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4. Chemical Symbols See Table 2 - "List
of Elements by
For convenience, elements have a symbol which is used as a Name"
shorthand for writing the names of elements. The symbol for an
element is either one or two letters taken from the name of the
element. Note that some have symbols that are based on the
historical name of the element. For example, the symbols for silver
and gold are Ag and Au respectively. These come from the old Latin
names argentum and aurum. The symbol for mercury, Hg, comes
from the Greek hydrargyros which means "liquid silver."
F. Nomenclature Objective 1.03.06
1. Atomic Number
a. The number of protons in the nucleus of an atom.
b. All atoms of a particular element have the same atomic number.
c. Atomic numbers are integers.
d. Atomic number for hydrogen is 1.
e. A helium atom has two protons in the nucleus, which means that
its atomic number is 2.
f. Uranium has 92 protons in the nucleus, and has an atomic
number of 92.
2. Mass Number
a. The total number of protons plus neutrons in the nucleus of an
isotope of an element is called the mass number.
b. Since a proton has a mass of 1.0073 amu, we will give it a mass
number of 1.
c. The mass number for a neutron is also 1, since its mass is 1.0087
amu.
d. By adding the number of protons and neutrons we can determine
the mass number of the atom of concern.
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(1) A normal hydrogen atom has 1 proton, but no neutrons.
Therefore, its mass number is 1.
(2) A helium atom has 2 protons and 2 neutrons, which means it
has a mass number of 4.
(3) If a uranium isotope has 146 neutrons, then it has a mass
number of 238 (92 + 146). If it only has 143 neutrons its
mass number would be 235.
e. The mass number can be used with the name of the element to
identify to which isotope of an element we are referring, such as
Uranium-235, Uranium-238 (often shortened to U-235 and
U-238).
3. Atomic Mass
a. The actual mass of a particular isotope.
b. The units are expressed in Atomic Mass Units (AMU)
(1) AMUs are based on 1/12 of the mass of a carbon-12 atom,
which has an atomic mass of 12 amu.
(2) The mass of a hydrogen atom is 1.007825 amu (1 proton + 1
electron)
(3) The mass of a Uranium-238 atom is 238.0508 and the mass
of a U-235 atom is 235.0439.
4. Atomic Weight
a. Average weight of an element based on the percent abundance of
its naturally occurring isotopes
(1) using 13
6 C and 12
6 C
(2) 12.00 (0.989) + 13.00 (0.011) = 11.868 + 0.143 = 12.011
amu.
b. Units are expressed in AMU
c. Used in calculations of chemical reactions
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G. Nuclide Notation
1. Z
Ax format where:
a. X is the symbol for the element.
b. Z is the atomic number - the number of protons.
c. A is the mass number - number of protons (Z) plus the number
of neutrons (N); therefore, A=Z+N
2. Uranium-238 would be written 238
92U
H. Modern Periodic Table
1. The modern Periodic Table is an arrangement of the elements in
order of increasing atomic number. A comparison of the properties
for selected elements will illustrate that there is a predictable,
recurring pattern (periodicity). This observation is summarized in
the Periodic Law - the properties of the elements are repetitive or
recurring functions of their atomic numbers.
Section 29
2. Data about each element in the Periodic Table are present in a
column and row format. The rows or horizontal sections in the
Periodic Table are called periods. The columns or vertical sections
in the Periodic Table are called groups or families.
3. The structure of the Periodic Table is directly related to the
arrangement of electrons in the atoms.
4. Electrons orbit around the nucleus in structured shells, designated
sequentially as 1 through 7 (K through Q) from inside out. Shells
represent groups of energy states called orbitals. The higher the
energy of the orbital the greater the distance from the nucleus. The
lowest energy state is in the innermost shell (K).
5. The number of orbitals in a shell is the square of the shell number
(n). The maximum number of electrons which can occupy an orbital
is 2. Therefore, each shell can hold a maximum of 2n2 electrons. For
example, for the L shell the maximum number of electrons would be
8:
L-shell: n = 2 → 2(22) = 8
Objective 1.03.07
See Fig. 5 -
"Periodic Table of
The Elements"
Objective 1.03.08
Objective 1.03.09
See Table 3 -
"Electron
Configuration of
the Elements"
See Fig. 4 -
"Electron Shells"
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6. The highest occupied energy level in a ground-state atom is called its
valence shell. Therefore, the electrons contained in it are called
valence electrons. The rows or periods in the Periodic Table
correspond to the electron shells. The elements contained in first
period have their valence electrons in the first energy level or
K-shell. The elements contained in the second period have their
outer or valence shell electrons in the second energy level or L-shell,
and so on.
7. The number of electrons in the valence shell determines the chemical
properties or "behavior" of the atom. The valence shell can have a
maximum of eight electrons, except for the K-shell which can only
have two. Atoms are chemically stable when the valence shell has
no vacancies; that is, they "prefer" to have a full valence shell.
Atoms of elements toward the right of the Periodic Table seem to
lack only one or two electrons. These will "look" for ways to gain
electrons in order to fill their valence shell. Atoms of elements on
the left side of the table seem to have an excess of one or two
electrons. These will tend to find ways to lose these excess electrons
so that the full lower shell will be the valence shell.
8. The outcome is that certain atoms will combine with other atoms in
order to fill their valence shells. This combination that occurs is
called a chemical bond, and results in the formation of a molecule.
The bond is accomplished by "sharing" or "giving up" valence
electrons, thus forming a molecule whose chemical properties are
different than those of the individual element atoms.
a. Good example - table salt
9. Note the right most column in the Periodic Table. These elements
are known as the noble or inert gases because they all have a full
valence shell. This means that they "feel" no need to bond with other
atoms. Noble gases are thus considered chemically inert and very
rarely interact with other elements.
10. The Quantum Mechanical Model
Objective 1.03.10
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Section 30
a. Over the years, the Bohr model of the atom was found
to be inadequate as the principles of quantum
mechanics evolved. A newer model, known as the
quantum mechanical model, describes the electrons
arranged in energy levels corresponding to the
"electron shells" of the Bohr model. In the quantum
mechanical model the electron is not viewed as particle
in a specific orbit, but rather as an electron cloud in
which the negative charge of the electron is spread out
within the cloud. These energy levels are referred to as
orbitals to emphasize that these are not circular "orbits"
like those of the Bohr model but rather electron clouds.
An electron cloud is a representation of the volume
about the nucleus in which an electron of a specific
energy is likely to be found.
b. The quantum mechanical model further states that the
energy levels are subdivided into sublevels, referred to
by the letters s, p, d and f. An energy level can contain
1 to 4 sublevels or orbitals, and a maximum of two
electrons can reside in each sublevel. For example, the
first energy level contains one s sublevel which can
accommodate a maximum of two electrons.
III. SUMMARY
A. Review major topics
1. Physics definitions
2. Law of Conservation of Energy
3. The Atom
4. Periodic Table
5. Valence Electrons
B. Review learning objectives
IV. EVALUATION
Evaluation should consist of a written examination comprised of multiple
choice questions. 80% should be the minimum passing criteria for the
examination.
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Module 1.04 Nuclear Physics Instructor’s Guide
Course Title: Radiological Control Technician
Module Title: Nuclear Physics
Module Number: 1.04
Objectives:
1.04.01 Identify the definitions of the following terms:
a. Nucleon
b. Nuclide
c. Isotope
1.04.02 Identify the basic principles of the mass-energy equivalence concept.
1.04.03 Identify the definitions of the following terms:
a. Mass defect
b. Binding energy
c. Binding energy per nucleon
1.04.04 Identify the definitions of the following terms:
a. Fission
b. Criticality
c. Fusion
References:
1. "Basic Radiation Protection Technology"; Gollnick, Daniel; 5th ed.; Pacific Radiation
Corporation; 2008.
2. "Introduction to Health Physics"; Cember, Herman; 4nd ed.; McGraw-Hill Medical; 2008.
3. ANL-88-26 (1988) "Operational Health Physics Training"; Moe, Harold; Argonne
National Laboratory, Chicago.
Instructional Aids:
1. Overheads
2. Overhead projector and screen
3. Chalkboard/whiteboard
4. Lessons Learned
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Module 1.04 Nuclear Physics Instructor’s Guide
I. MODULE INTRODUCTION
A. Self-Introduction
1. Name
2. Phone number
3. Background
4. Emergency procedure review
B. Motivation
This lesson is designed to provide an understanding of the
forces present within an atom.
C. Overview of Lesson
1. Nucleon
2. Nuclide
3. Isotope
4. Mass-Energy Equivalence
5. Mass Defect
6. Binding Energy
7. Fission
8. Criticality
9. Fusion
D. Introduce Objectives O.H.: Objectives
II. MODULE OUTLINE
Objective 1.04.01A. Nuclear Terminology
1. Nucleon - a constituent particle of the nucleus, either a
proton or a neutron
2. Nuclide
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a. Atoms with a specific combination of neutrons and
protons
b. Nuclides have individual blocks on the Chart of the
Nuclides
3. Isotope
a. Have the same number of protons but different
number of neutrons
Section 31
b. Same atomic number but different atomic mass
number
c. Isotopes of Hydrogen have one proton; however, the
atomic mass number is different
d. Protium (1H) has A=1, deuterium (2H) has A=2,
tritium (3H) has A=3
B. Mass - Energy Equivalence
Objective 1.04.02
1. Theory on Relativity developed by Albert Einstein in
1905
2. Equation: Write equation on board
E = mc2
where:
E = Energy
m = mass
c = speed of light
3. Mass may be transformed to energy and vice versa
4. Mass and energy are interchangeable
5. The mass of an object depends on its speed
6. Matter contains energy by virtue of its mass
7. Energy/Mass cannot be created or destroyed, only
converted
Information only
8. Pair Annihilation (Mass to Energy example)
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a. When a positron and electron collide, both particles
are annihilated and their mass is converted to energy
b. Mass of electron/positron is 0.00054858026 amu,
annihilation energy will be:
2(0.00054858026 amu) 931.478 MeV
× = 1.022 MeV
1 amu
C. Mass Defect/Binding Energy
1. Mass Defect
a. Difference between the sum of the protons and
neutrons and the actual mass of a nuclide
b. Equation:
∗ = (Z)(Mp) + (Z)(Me) + (A-Z)(Mn) - Ma
Where:
∗ = mass defect
Z = atomic number
Mp = mass of a proton (1.00728 amu)
Me = mass of a electron (0.000548 amu)
A = mass number
Mn = mass of a neutron (1.00867 amu)
Ma = atomic mass (from Chart of the Nuclides)
c. Example for 2
3 Li :
1) A = 7
Z = 3
M = 7.01600 amu
2) Therefore:
∗ = (3)(1.00728) + (3)(0.000548) + (7-3)(1.00867)
(7.01600)
∗ = (3.02184) + (0.001644) + (4.03468) - (7.01600)
∗ = (7.058164) - (7.01600)
∗ = 0.042164 amu
(1 amu = 931.478 MeV)
Objective 1.04.03
See Fig. 1 "Atomic Scale"
Work example on board
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2. Binding energy
a. The energy equivalent of mass defect
b. Example for 7
3Li :
0.042164 amu 931.478 MeV
BE = × = 39.72 MeV
1 amu
3. Binding energy of a neutron
a. Energy added to a nucleus by adding the mass of a
single neutron
b. Must be calculated for each isotope to determine
value
c. Example for 235U:
Δm = (mn + mU235) - mU236
Δm = (1.00867 + 235.0439) - 236.0456
Δm = 0.0070 amu
0.0070 amu × 931.5 MeV/amu = 6.52 MeV
4. Binding energy per nucleon
a. Calculated by dividing the total binding energy of an
isotope by its mass number
b. Example for 7
3Li :
39.27 MeV
= 5.61 MeVpernucleon
7nucleons
c. Peaks at about 8.5 MeV for mass numbers 40 – 120
5. Nuclear Transformation Equations (Q Value)
Example alpha decay for 226Ra:
226 222 4Ra ⎯⎯ α + Q→ Rn + 88 86 2
D. Terminology
1. Fission
Work example on board
(1 amu = 931.478 MeV)
Work example on board
See Fig. 2 "Binding Energy vs. Mass
Number"
Work example on board
Objective 1.04.04
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a. Splitting of a nucleus into at least two other nuclei
with the release of energy
b. Two or three neutrons are generally released
c. Liquid drop model
1) Equates the nucleus with a drop of water
2) Each contains cohesive forces
3) When forces are overcome, the water drop/atom
will split/fission
d. Fissile nuclei
1) Neutron binding energy must exceed critical
energy for fission
2) Critical energy for fission (Ec): The energy
required to drive the nucleus to the point of
separation.
3) No kinetic energy required by the neutron
Section 32
4) Fissile nuclei: 235U, 233U, 239Pu
e. Fissionable nuclei
1) Neutron binding energy not enough to exceed
critical energy for fission
2) Kinetic energy required to cause fission
3) 238U, 232Th
f. Energy released
1) Makes two smaller nuclei from one large
nucleus
2) Binding energy per nucleon increases
3) Approximately 200 Mev released per fission (for
235U)
g. Fission product
See Fig. 3 "Liquid Drop Model of
Fission"
See Fig. 4 "235U Fission Process"
Fertile material is a term used to
describe nuclides which generally
themselves do not undergo induced
fission (fissionable by thermal
neutrons) but from which fissile
material is generated by neutron
absorption and subsequent nuclei
conversions. Fertile materials can
occur naturally and can be converted
into a fissile material by irradiation
in a reactor.
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1) Created during fission
2) Normally unstable - N/P ratio too high
3) Will undergo radioactive decay until stable -
May take less than a second to several hundred
years to reach stability
2. Criticality
a. Criticality is the condition in which the number of See Fig. 5 "Chain Reaction"
neutrons produced by fission is equal to the number
of neutrons produced in the previous generation
b. The effective multiplication constant or Keff is See Table 1 - "The Effective
defined as the ratio of the number of neutrons in the Multiplication Constant"
reactor in one generation to the number of neutrons
in the previous generation.
1) Subcritical - Keff < 1
2) Critical - Keff = 1
3) Supercritical - Keff > 1
3. Fusion
a. Fusion builds atoms
b. The process of fusing nuclei into a larger nucleus
with an accompanying release of energy
c. Change of mass
d. Energy released
III. SUMMARY
A. Review major topics
1. Nucleon
2. Nuclide
3. Isotope
4. Mass-Energy Equivalence
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Module 1.04 Nuclear Physics Instructor’s Guide
5. Mass Defect
6. Binding Energy
7. Fission
8. Criticality
9. Fusion
B. Review learning objectives
IV. EVALUATION
Evaluation should consist of a written examination comprised of
multiple choice questions. 80% should be the minimum passing
criteria for the examination.
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DOE-HDBK-1122-2009
Module 1.05 Sources of Radiation Instructor’s Guide
Course Title: Radiological Control Technician
Module Title: Sources of Radiation
Module Number: 1.05
Objectives:
1.05.01 Identify the following four sources of natural background radiation including the origin,
radionuclides, variables, and contribution to exposure.
a. Terrestrial
b. Cosmic
c. Internal Emitters
d. Radon
1.05.02 Identify the following four sources of artificially produced radiation and the magnitude of
dose received from each.
a. Nuclear Fallout
b. Medical Exposures
c. Consumer Products
d. Nuclear Facilities
References:
1. "Basic Radiation Protection Technology"; Gollnick, Daniel; 5th ed.; Pacific Radiation
Corporation; 2008.
2. ANL-88-26 (1988) "Operational Health Physics Training"; Moe, Harold; Argonne
National Laboratory, Chicago.
3. NCRP Report No. 45 "Natural Background Radiation in the United States".
4. NCRP Report No. 56 "Radiation Exposure from Consumer Product Miscellaneous
Sources".
5. NCRP Report No. 160 "Ionizing Radiation Exposure of the Population of the United
States".
Instructional Aids:
1. Overheads
2. Overhead projector/screen
3. Chalkboard/whiteboard
4. Lessons Learned
Section 33
I. MODULE INTRODUCTION
A. Self-Introduction
1. Name
2. Phone number
3. Background
4. Emergency procedure review
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Module 1.05 Sources of Radiation Instructor’s Guide
B. Motivation
1. Radiation sources are not limited to nuclear facilities. The study of
sources provides data for:
a. Basis for occupational exposures
b. Effects from high source exposures
c. Assesses impact from nuclear facilities
d. Determines use of building materials
C. Overview of Lesson
1. Terrestrial radiation
2. Cosmic radiation
3. Internally emitted radiation
4. Radon
5. Nuclear fallout
6. Medical exposures
7. Consumer products
8. Nuclear facilities
O.H.: Objectives
D. Introduce Objectives
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Module 1.05 Sources of Radiation Instructor’s Guide
II. MODULE OUTLINE
A. Natural Background Radiation Sources
1. Terrestrial Radiation
a. Earth
1) Source - small amounts of radioactive material found in rock
and soil
2) Major isotopes: Uranium and Thorium
3) Exposure dependent on location
Atlantic and Gulf coastal = 15-35 mrem/yr
Greater U.S. = 35-75 mrem/yr
Colorado Plateau = 75-140 mrem/yr
4) Exposure dependent on type of soil
Volcanic - 125 mrem/yr
Sandstone - 50 mrem/yr
Limestone - 25 mrem/yr
5) U.S. average: 1 sq mile 1 ft deep contains 1 ton K-40, 3 tons
U-238, 6 tons Th-232
6) Extremely high locations - due to high concentrations of
monazite:
Kerala India - Population is 70K
16K receive >500 mrem/yr
500 receive >2,000 mrem/yr
Highest: 5,865 mrem/yr
Minas Garais Brazil
Average: 1,160 mrem/yr
Max: 12,000 mrem/yr
b. Radioactivity in Water
1) All water contains some radioactivity
Objective
1.05.01 a.
Explain: Different
books will use
other dose rates.
The references
used here are
NCRP reports.
Monazite: a
Thorium Mineral
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Module 1.05 Sources of Radiation Instructor’s Guide
2) Examples
Sea water contains K-40
Natural springs contain U and Th
Rainwater picks up radioactivity from the air
Ground water picks up radioactivity from the soil Contributor
to internal doses
c. U.S. average of alpha emitters in water is <1 pCi/l
1) Colorado – 40-50 pCi/l
2) Brazil – 240 pCi/l (bottled water)
d. U.S. national average from terrestrial (NCRP Report No. 95) is
28 mrem/yr
Objective
2. Cosmic Radiation 1.05.01 b.
a. Natural radiation originating from outside of our atmosphere
b. Discovered during early terrestrial experiments with weather
balloons
c. Primary
1) Galactic Cosmic Rays
From outside the solar system
Positively charged particles
• 87% protons
• 11% alpha
• 2% misc.
High energies - up to 1020 eV
2) Geomagnetically Trapped
When galactic rays approach earth, they must have enough
energy to pass through magnetic fields
If they lack enough energy, they become trapped in two
energy bands
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Module 1.05 Sources of Radiation Instructor’s Guide
• 1K - 3K meters
• 12K - 15K meters
3) Solar Cosmic Rays
Produced by severe solar flares
Consist mainly of protons
High energy - detected on ground
Low energy - detected at high alt.
Measurements
• 30,000 ft - 100 mr/hr
• 80,000 ft - 10 R/hr
Concern for high altitude space travel
d. Secondary
1) Results from the interaction of primaries with the earth's
atmosphere
2) Cascade effect: one primary ionization = 100 million
secondary ionizations
3) Products produced: pions, muons, electrons, photons,
Section 34
protons, neutrons
4) Primaries absorbed within the upper 10% of the atmosphere
5) Dominant components at ground level are penetrating muons
and the electrons they produce.
6) Latitude contributes a small factor due to the earth's magnetic
field
7) Exposures increase with altitude, decrease with latitude
(Denver 50 mr/yr cosmic)
8) U.S. average = 27 mrem/yr
Objective3. Internal Emitters (Food Chain)
1.05.01 c.
a. Results from the transfer of natural radiation from the food chain
to man
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Module 1.05 Sources of Radiation Instructor’s Guide
b. Deposited internally from trace amounts found in soil, water and
air
c. Isotopes: Primary - K-40
others - Rb-87, Ra-226, U-238, Po-210, C-14
d. U.S. national average is 39 mrem/yr from Internal Emitters
4. Radon
a. Due mostly to Radon and thoron gas
b. Radon is a product of the U-238 Series
U-238 6 Th-234 6 Pa-234 6 U-234 6 Th-230 6
Ra-226 6 Rn
c. Thoron is a product of the Th-232 series
Th-232 6 Ra-228 6 Ac-228 6 Th-228 6 Ra-224 6
Rn-220
d. U and Th are present all over. Daughter products diffuse to the
surface. These gases attach themselves to dusts and aerosols
which are inhaled.
e. Radon concentrations are based on amounts of U and Th in the
area
f. Factors:
• Weather (inversions)
• Indoor insulation
• Ventilation rate
g. High Areas:
Most has been• Colorado (Grand Junction) – mine tailings removed • Pennsylvania – High radium concentration
• Underground mines, caves, caverns, etc.
• Helsinki – 240 rem to lung from radon
h. U.S. national average for inhaled radionuclides is 200 mrem/yr.
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Module 1.05 Sources of Radiation Instructor’s Guide
Objective
B. Man Made Background Radiation Sources 1.05.02 a.
1. Nuclear Fallout
a. Refers to the debris that settles as a result of weapons testing
b. Contains over 200 fission products, bomb parts and all near-blast
matter
c. Dispersement is a function of:
1) Bomb yield
Kiloton Range - troposphere, 9,000 - 17,000 meters - easily
washed down
Megaton Range - Stratosphere, may stay aloft for five years
2) Types of blast
Surface burst
Above ground
3) Meteorological Factors - (weather)
d. Weapons test ban treaty of 1962-63 limited testing
e. U.S. average from nuclear fallout is <1 mrem/yr (NCRP #93)
2. Medical Exposures
Objective
a. Diagnostic X-rays 1.05.02 b.
1) Over 300,000 X-ray units in the U.S., about 67% of adult
population is exposed each year
2) X-ray machines consist of:
a) X-ray tube
b) HV Supply
c) Filament
d) Shielding
3) Three general types:
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Module 1.05 Sources of Radiation Instructor’s Guide
a) Radiography - X-ray tube and a photographic plate
(Chest, Dental)
b) Fluoroscope - Uses an image intensifier, observes internal
processes
c) Photofluorographic - Fluorescent screen and camera, large
amounts of people
b. Medical Radionuclides (Two Types)
1) Nuclear Medicine
Used to diagnose medical problems
Attaches a radionuclide to a pharmaceutical that will seek a
particular organ
• Radionuclide selection:
• Photon emitter
• Short lived
Tc-99m, In-113m
2) Radiation Oncology
Uses high energy power source to treat tumors
Typical 6,000 Curie Co-60 source delivers 100 Rad/min
3) NCRP Report No. 160 gives the dose equivalent for medical
radionuclides as ~ 300 mrem/yr
1) computed tomography (total average dose ~ 150
mrem/yr)
2) nuclear medicine (total average dose ~ 75 mrem/yr)
Section 35
3) radiography/fluroscopy (total average dose ~ 75
mrem/yr)
Objective3. Consumer Products (NCRP Report 56)
1.05.02 c.
a. Television (Example)
1) Source -- X-rays from High Voltage a few.
2) Limit (1960) -- 0.5 mr/hr at 5 cm
3) 1967 - 149 big screen TVs were recalled, 2 emitted greater
than 100 mRad/hr
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Module 1.05 Sources of Radiation Instructor’s Guide
4) U.S. average -- 0.5 to 1.5 mr/yr
b. Shoe fitting fluoroscopes (Example)
1) Source - X-ray tube
2) 1953 - 10,000 in use
3) Exposures - 7 to 14 R per 20 sec exposure GSD - 30 to 170 mr
c. Radioluminous Watches (Example)
1) Source - Ra-226 "Glow in the Dark"
2) 10,000,000 still in use
3) Pr-147 and H-3 used today
d. Hundreds of other products contribute
1) U.S. national average from all consumer products is
10 mrem/yr
4. Nuclear Facilities
a. Public exposures from
1) Mining (several hundred) and milling (20 mills)
Objective
2) Fuel Fabrication (21 facilities) 1.05.02 d.
3) Reactors (~90 power, 300 non-power)
b. U.S. national average - <1 mrem/yr
C. Total Background Radiation
The average annual total effective dose to the general population (non
smokers) from naturally occurring and manmade sources is about 620 mrem.
III. SUMMARY
A. Review major topics
1. Terrestrial radiation
2. Cosmic radiation
3. Internally emitted
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Module 1.05 Sources of Radiation Instructor’s Guide
4. Radon
5. Nuclear fallout
6. Medical exposures
7. Consumer products
8. Nuclear facilities
B. Review learning objectives
IV. EVALUATION
Evaluation should consist of a written examination comprised of multiple
choice questions. 80% should be the minimum passing criteria for the
examination.
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Module 1.06 Radioactivity and Radioactive Decay Instructor’s Guide
Course Title: Radiological Control Technician
Module Title: Radioactivity & Radioactive Decay
Module Number: 1.06
Objectives:
1.06.01 Identify how the neutron to proton ratio is related to
nuclear stability.
1.06.02 Identify the definition for the following terms:
a. radioactivity
b. radioactive decay
c.
1.06.03 Identify the characteristics of alpha, beta, and gamma
radiations.
1.06.04 Given simple equations identify the following radioactive
decay modes:
a. alpha decay
b. beta decay
c. positron decay
d. electron capture
1.06.05 Identify two aspects associated with the decay of a
radioactive nuclide.
1.06.06 Identify differences between natural and artificial
radioactivity.
1.06.07 Identify why fission products are unstable.
1.06.08 Identify the three naturally-occurring radioactive families
and end product of each.
1.06.09 Given a nuclide, locate its block on the Chart of the
Nuclides and identify the following for that nuclide:
a. atomic number
b. atomic mass
c. natural percent abundance
d. stability
e. half-life
f. types and energies of radioactive emissions
1.06.10 Given the Chart of Nuclides, trace the decay of a
radioactive nuclide and identify the stable end-product.
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1.06.11 Identify the definition of the following units:
a. curie
b. becquerel
1.06.12 Identify the definition of specific activity.
1.06.13 Identify the definition of half-life.
1.06.14 Calculate activity, time of decay, and radiological half life
using the formula for radioactive decay.
Section 36
1.06.15 Identify the definition of the following:
a. exposure
b. absorbed dose
c. equivalent dose
d. radiation weighting factor
1.06.16 Identify the definition of the following units:
a. roentgen
b. rad/gray
c. rem/sievert
References:
1. "Training Publication 89n, Training Publication 30n"; GPO
Division of Radiological Health.
2. ANL-88-26 (1988) "Operational Health Physics Training"; Moe,
Harold; Argonne National Laboratory, Chicago.
3. "Health Physics and Radiological Health Handbook"; Shleien;
1992.
4. "Chart of the Nuclides"; Sixteenth Edition, Knolls Atomic; 2003.
5. "Basic Radiation Protection Technology"; Gollnick, Daniel; 5th
ed.; Pacific Radiation Corporation; 2008.
6. DOE/HDBK-1019 (January 1993) "Nuclear Physics and Reactor
Theory" Volume 1 of 2; DOE Fundamentals Handbook Series.
Instructional Aids:
1. Overheads
2. Overhead projector/screen
3. Chalkboard/whiteboard
4. Lessons learned
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Module 1.06 Radioactivity and Radioactive Decay Instructor’s Guide
I. MODULE INTRODUCTION
A. Self Introduction
1. Name
2. Phone number
3. Background
4. Emergency procedure review
B. Motivation
Atoms consist of protons, neutrons, and electrons and only certain
combinations of protons and neutrons exist in nature. Specific
combinations of protons and neutrons within the nucleus determine
whether nuclei are stable or unstable. Stable nuclei have no excess
energy, while unstable nuclei, due to their surplus energy, transform
themselves into stable nuclei by giving up energy. The emission of this
extra energy to achieve stability is the phenomenon of radioactivity.
C. Overview of Lesson
1. Neutron to proton ratio
2. Radioactivity and radioactive decay
3. Radiation characteristics
4. Decay modes
5. Natural/artificial radioactivity
6. Fission product stability
7. Chart of the nuclides
8. Units of activity
9. Activity calculation
10. Measurement terminology
D. Introduce Objectives O.H.: Objectives
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Module 1.06 Radioactivity and Radioactive Decay Instructor’s Guide
II. MODULE OUTLINE
A. Nuclear Stability
1. Forces in the Nucleus
a. Gravitational Force: very weak attractive force between all
nucleons; acts over a relatively long range.
b. Electrostatic Force: a strong repulsive force between like
charged particles (protons); acts over a relatively long range.
c. Nuclear Force: a strong attractive force between all nucleons;
acts over an extremely short range.
d. In stable atoms the attractive and repulsive forces balance (are
equal). If forces are not balanced the nucleus will be unstable.
2. Neutron/Proton Ratio
a. Only certain combinations or ratios of neutrons and protons
will result in a balance of these forces (stable).
b. For atomic numbers less than 20, the neutron to proton ratio
(n:p) is about 1:1.
c. As number of protons is increased, the electrostatic force
increases. The numbers of neutrons must increase more rapidly
in order for the nuclear force to balance with electrostatic force.
d. As Z increases above 20 the n:p ratio gradually increases until
Z = 83, where stable ratio is about 1.5:1.
e. There are no completely stable nuclei with Z > 83.
f. By graphing the numbers of neutrons against the number of
protons for stable isotopes, a "line of stability" is depicted.
3. Stability Ranges
a. Nuclear stability is governed by the particular combination of
neutrons and protons in a given nucleus.
Section 37
Objective 1.06.01
See Table 1 -
"Forces
Acting in the
Nucleus"
See Fig.1 -
"Neutron:Proton
Ratios
for Stable Nuclides"
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Module 1.06 Radioactivity and Radioactive Decay
b. Because many elements have several stable isotopes, there is a
range for numbers of neutrons that will be stable in a nucleus
with a certain number of protons.
Instructor’s Guide
c. A nuclear arrangement outside of this range will be unstable.
An unstable nucleus will attempt to become stable by changing
its nuclear configuration.
d. Nuclear configuration is changed by eliminating excess
neutrons or protons, thereby changing the n:p ratio becoming
more stable.
B. Radioactivity
Objective 1.06.02
1. Definitions
a. Nuclear configuration changes occur through transformations.
This is done by changing neutrons to protons, or vice versa and
then ejecting the surplus mass or energy from the nucleus.
b. Particles or energy emitted from the nucleus is called radiation.
Radiation can be in the form of particles or waves.
c.
d.
The property of certain radionuclides to spontaneously emit
radiation is called radioactivity. In other words, if a nuclide has
this property it is said to be radioactive. The term radionuclide
has been coined to refer to these "radioactive nuclides."
The emission of a particle or electromagnetic radiation in order
to reach a more stable configuration produces a change or
transformation.
The term
radionuclide has
been coined to refer
to these
"radioactive
nuclides."
e. Following a transformation the nucleus is usually more stable
than it was, but it may not be completely stable. So, another
transformation will take place in which the nucleus will again
emit radiation.
f. The amount of energy given off and the type of emission that
occurs will depend on the configuration of the nucleus
immediately before a specific transformation occurs. Each step
in the series of transformations will mean a distinct reduction in
total mass-energy of the nucleus.
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Module 1.06 Radioactivity and Radioactive Decay Instructor’s Guide
g. As the energy of the nucleus is reduced, the nucleus is said to
disintegrate or decay. The process by which a nucleus
spontaneously disintegrates (or is transformed) by one or more
discrete energy steps until a stable state is reached is called
radioactive decay.
h. The nucleus before the decay (or transformation) is called the
parent and the nucleus after the decay is called the daughter.
i. When there are a series of transformations before a stable state
is reached, the daughter of one decay may also be radioactive
and thus be the parent to another daughter.
j. As the various steps from parent to daughter are traced to
stability, a series of transmutations is seen, called a decay
chain. The complete chain includes the original parent, all of its
daughters and the final, stable endproduct.
2. Nature of Radioactivity
a. Certain nuclides are unstable as they occur in nature and are
therefore referred to as being naturally radioactive, while others
are artificially radioactive because they have become
radioactive as a result of some man-made reaction.
b. Evidence of natural radioactivity was first reported by Henri
Becquerel in 1896. Becquerel demonstrated that uranium ore
would darken a photographic plate shielded with opaque paper
in much the same manner as X-rays. He postulated that the
uranium emitted very penetrating rays, similar to X-rays.
Section 38
c. The phenomenon ultimately was called radioactivity. In time, it
was determined that there were many elements beyond the
atomic number of lead (Z=82) which showed similar radiating
characteristics.
d. After a long and complicated series of investigations, to which
many outstanding physicists contributed, a better understanding
of natural radioactivity was available.
e. The understanding culminated with the experiments of Ernest
Rutherford. In 1903, he clearly showed there were three kinds
of radioactive emissions, which he named alpha, beta, and
gamma, after the first three letters of the Greek alphabet.
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C. Modes of Decay and Types of Radioactive Emissions
1. As mentioned above, Rutherford was initially able to identify three Objective 1.06.03
types of radiation resulting from radioactive decay: alpha, beta and
gamma. Initially, all three radiations were commonly referred to as
rays.
2. With time, the characteristics of each of these radiations was
determined. It was found that alpha and beta are actually particulate
radiations, not rays. Since then, other radiations have been
discovered through numerous experiments and tests.
3. When a radioactive nuclide decays, a transmutation occurs. The
decay product, or daughter has become an atom of a new element
with chemical properties entirely unlike the original parent atom.
With each transmutation an emission from the nucleus occurs. There
are several modes of decay and emissions associated with each
mode.
4. Alpha Decay
a. With a few exceptions, only relatively heavy radioactive Objective 1.06.04 a.
nuclides decay by alpha emission.
b. An alpha particle is essentially a helium nucleus. It consists of
two protons and two neutrons, giving it a mass of 4 amu.
c. Because of the two protons it has an electric charge of +2.
d. The symbol α is used to designate alpha particles.
e. A nucleus emitting an alpha particle decays to a daughter
element, reduced in atomic number (Z) by 2 and reduced in mass
number (A) by 4. The standard notation for alpha decay is:
f. For example, Radium-226 decays by alpha emission to produce
Radon-222 as follows:
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g. Alpha particles are the least penetrating of the three types of
radiation. They can be absorbed or stopped by a few centimeters
of air or a sheet of paper.
5. Beta Decay Objective 1.06.04 b.
a. A nuclide that has an excess number of neutrons (i.e. the n : p
ratio is high) will usually decay by beta emission. The
intranuclear effect would be the changing of a neutron into a
proton, thereby decreasing the n:p ratio, resulting in the emission
of a beta particle.
b. Beta particles are negatively charged particles. They have the
same mass as an electron (1/1836 of proton or 5.49E-4 amu) as
well as the same charge (-1) and can be considered high speed
electrons.
c. Because of the negative charge of the beta particle, beta
emission is often more explicitly referred to as "beta-minus"
emission (the particle sometimes being referred to as a
negatron).
d. Beta particles originate in the nucleus, in contrast with ordinary
electrons, which exist in orbits around the nucleus.
e. The symbol β- is used to designate beta particles.
f. In beta-minus emitters, the nucleus of the parent gives off a
Section 39
negatively charged particle, resulting in a daughter more positive
by one unit of charge. Because a neutron has been replaced by a
proton, the atomic number increases by one, but the mass
number is unchanged.
g. In order to conserve energy and momentum between the parent
and the daughter plus beta particle there is also the emission of
an antineutrino, symbolized by the Greek letter nu with a bar
above it ( ) .v
h. The standard notation for beta decay is:
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Module 1.06 Radioactivity and Radioactive Decay
i. For example, Lead-210 decays by beta-minus emission to
produce Bismuth-210 as follows:
Instructor’s Guide
j. Beta particles are emitted with kinetic energies ranging up to the
maximum value of the decay energy, Emax. The average energy
of beta particles is about 1/3Emax.
k. They travel several hundred times the distance of alpha particles
in air and require a few millimeters of aluminum to stop them.
1. Neutrinos (ν) and anti-neutrinos ( )v are neutral (uncharged)
particles with negligible rest mass, travel at the speed of light
and are very non-interacting. They account for the energy
distribution among positrons and beta particles from given
radionuclides in the positron- and beta-decay processes
respectively.
6. Positron Decay Objective 1.06.04 c.
a. A nuclide that has a low n : p ratio (too many protons) will tend
to decay by positron emission.
b. A positron is often mistakenly thought of as a positive electron.
If positive electrons existed, then when they encountered an
ordinary negative electron, the Coulomb force would cause the
two particles to accelerate toward each other. They would collide
and then the two equal but opposite charges would mutually
cancel. This would leave two neutral electrons.
c. Actually, a positron is the anti-particle of an electron. This
means that it has the opposite charge (+1) of an electron (or beta
particle). Thus, the positron is a positively charged, high-speed
particle which originates in the nucleus.
d. Because of its positive charge and a rest mass equal to that of a
beta particle, a positron is sometimes referred to as "beta-plus."
e. The symbol β+ is used to designate positrons.
f. With positron emitters, the parent nucleus changes a proton into
a neutron and gives off a positively charged particle.
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g. This results in a daughter less positive by one unit of charge.
Because a proton has been replaced by a neutron, the atomic
number decreases by one and the mass number remains
unchanged.
h. The emission of a neutrino (symbolized by ν) also occurs in
conjunction with the positron emission.
i. Positron decay is illustrated by the following notation:
j. For example, Nickel-57 decays by positron emission:
7. Electron Capture
a. For radionuclides having a low n : p ratio, another mode of
decay can occur known as orbital electron capture (EC).
b. In this radioactive decay process the nucleus captures an electron
from an orbital shell of the atom, usually the K shell, since the
electrons in that shell are closest to the nucleus. This mode of
decay is frequently referred to as K-capture. The nucleus might
conceivably capture an L shell electron, but K electron capture is
much more probable.
c. The transmutation resembles that of positron emission, as
follows:
d. The electron combines with a proton to form a neutron, followed
by the emission of a neutrino.
Section 40
e. Electrons from higher energy levels immediately move in to fill
the vacancies left in the inner, lower-energy shells. The excess
energy emitted in these moves results in a cascade of
characteristic X-ray photons.
f. Either positron emission or electron capture can be expected in
nuclides with a low n : p ratio.
g. The intranuclear effect of either mode of decay would be to
change a proton into a neutron, thus increasing the n : p ratio.
Objective 1.06.04 d.
The nucleus might
conceivably capture
an L shell electron,
but K electron
capture is much
more probable.
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h. Note that 57Ni has two modes of decay. This is an example of
branching which is explained in the section DECAY
PHENOMENA.
8. Gamma Emission
a. Gamma emission is another type of radioactive decay. Nuclear
decay reactions resulting in a transmutation generally leave the
resultant nucleus in an excited state. Nuclei, thus excited, may
reach an unexcited or ground state by emission of a gamma ray.
b. Gamma rays are a type of electromagnetic radiation. They
behave as small bundles or packets of energy, called photons,
and travel at the speed of light.
c. The symbol γ is used to designate gamma radiation.
d. Since the gamma decay doesn't involve the gain or loss or
protons or neutrons, the general equation is slightly different
from the other decay equations.
For all intents and
purposes, gamma
radiation is the
same as X-rays.
Gamma rays are
usually of higher
energy (MeV),
whereas X-rays are
usually in the keV
range. The basic
difference between
gamma rays and X-
rays is their origin;
gamma rays are
emitted from the
nucleus of unstable
atoms, while X-rays
originate in the
electron shells.
The basic difference
between gamma
rays and visible
light is their
frequency.
All of the
transmutation
examples given
could be
accompanied by
gamma emission.
Although most
nuclear decay
reactions do have
gamma emissions
associated with
them, there are
some radionuclide
species which decay
by particulate
emission with no
gamma emission.
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Module 1.06 Radioactivity and Radioactive Decay Instructor’s Guide
e. Table 2 provides a summary of the characteristics of the various
types of radioactive emissions that have been discussed. Table 3
summarizes the various modes of radioactive decay.
9. Other Types of Transformations
a. Internal conversion
1) This phenomenon occurs when a gamma photon does not
escape the electron cloud surrounding the nucleus, but
transfers to one of the orbital electrons enough energy to
eject it from the atom.
2) The photon is said to have undergone internal conversion.
3) The conversion electron is ejected from the atom with
kinetic energy equal to the gamma energy minus the binding
energy of the orbital electron.
4) This process usually takes place in the K-shell. There will
then follow emission of characteristic X-rays as with
electron capture.
b. Isomeric transition
1) Isomeric transition commonly occurs immediately after
particle emission; however, the nucleus may remain in an
excited state for a measurable period of time before dropping
to the ground state at its own characteristic rate.
2) A nucleus that remains in such an excited state is known as
an isomer because it is in a metastable state; that is, it differs
in energy and behavior from other nuclei with the same
atomic number and mass number.
Section 41
3) The metastable or excited state, is usually represented by a
small m following the mass number, A, in the standard
nuclide notation.
4) For example, Technetium-99m and Technetium- 99 are
isomers. 99mTc will decay 99 Tc with the emission of a
43 43
140.5 keV gamma.
See Table 2 -
"Types of
Radioactive
Emissions"
and Table 3 -
"Modes of
Decay"
In principle,
internal
conversion is
similar to
the photoelectric
effect (to
be discussed in
Lesson
1.07).
Generally, the
isomer
achieves ground
state by
emitting delayed
(usually
greater than 10-9
seconds)
gamma radiation.
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Further radioactive decay can still occur from the ground
state. In this case, 99Tc decays to 99Ru, which is stable.
D. Decay Phenomena
1. Each radionuclide, artificial and natural, has its own characteristic
pattern of decay. There are several aspects associated with this
pattern:
a. Modes of decay
b. Types of emissions
c. Energies of the emissions involved
d. Rate of decay
2. Mode of Decay
a. All nuclei of a given radionuclide seeking stability by
radioactive decay do so in a specific manner.
b. There are some radioactive nuclides which may decay with
branching, whereby a choice of decay modes exists. In such
case, a definite branching ratio exists.
A case in point is the decay of 57Ni, mentioned previously.
This isotope of nickel decays 50% by K-capture and 50% by
β+ emission. The branching ratio would be:
3. Types and energies of Emissions
a. Not only do various radionuclides disintegrate in a constant
manner insofar as the types of emissions are concerned, but the
emissions from each nuclide exhibit a distinct energy picture.
Objective 1.06.05
226Ra decays by
alpha emission
which is
accompanied by a
gamma photon.
This represents the
only mode of decay
open to 226Ra.
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b. The energies associated with radiations are given in terms of
"million electron volts" (MeV).
1) Beta emissions may occur with energies to about 5 MeV
2) Alpha particles to about 10 MeV
3) Gamma photons to about 3 MeV.
c. The energy of the particulate radiations is manifested as kinetic
energy--the higher the energy the greater the velocity of the
particle.
d. The velocity of photons is constant (c = speed of light) and
energy differences are manifested by varying wavelengths and
frequencies.
4. Rate of Decay
a. The other characteristic aspect associated with decay patterns is
the rate of decay, or activity. The disintegrations of
radionuclides occur with a regularity characteristic for each
particular species.
b. Such disintegrations are spontaneous and random. A single
radium nucleus, for instance, may disintegrate at once or wait
thousands of years before emitting an alpha particle.
c. All that can be predicted with any certainty is that half of all the
226Ra nuclei present will disintegrate in 1,622 years. This period
is called the half-life of 226Ra. Half-lives vary greatly for natural
occurring radioisotopes; e.g. 212Po, with a half life of 0.298
microseconds and 232Th, with a half-life of over 1.42E10 years.
5. Singly-occurring Natural Radionuclides
a. Careful measurements show that almost all materials contain
traces of radioactivity.
Section 42
b. One might suspect that these traces might be due to See Table 4 -
contamination with some of the heavy radionuclides belonging "Naturally
to one of the radioactive series described. However, some of the occurring
lighter elements are themselves weakly radioactive. Radionuclides"
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c. It may have been noted that Carbon-14 was not included as a
natural radionuclide in Table 4, even though it has received
considerable popular attention in recent years, as naturally-
occurring radiocarbon has been found in definite, though small,
proportions.
The 14C existing in the atmosphere is being
formed continually as a result of nuclear reactions
between atmospheric nitrogen and neutrons from
cosmic rays. This is shown in the following
reaction:
6. Artificial Radioactivity Objective 1.06.06
a. There are radionuclides which occur as a result of various man-
made reactions. These are called artificial radionuclides. The
vast majority of radionuclides are produced in this manner.
b. As implied in the nomenclature, natural and artificial
radioactivity differ in origin. There are other distinctions
between the two types which will be discussed.
c. Nevertheless, the nuclei of artificial radionuclides are unstable in
much the same manner as their natural counterparts. The
intranuclear factors governing decay are also similar for both
groups.
d. A brief account of the discovery of artificial radioactivity will be
given before further discussing its similarities and dissimilarities
to natural radioactivity.
7. Induced Transmutations
a. In 1919, Lord Rutherford demonstrated that it was possible to
produce artificially a transmutation of elements. The manner in
which naturally-occurring radioactive atoms are changed or
transmuted by emitting radiation has been discussed.
b. Lord Rutherford set up and observed a nuclear reaction in
reverse, one might say, whereby high-speed charged particles
(projectiles) bombarded stable atomic nuclei (target), resulting in
a reaction at the nuclear level and inducing a transmutation.
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c. Since the discovery of the transmutation of nitrogen, many
hundreds of artificial or induced transmutations have been
found. Until 1932, most induced transmutations were performed
utilizing naturally occurring alpha emitters as sources of incident
particles.
d. With the development of particle accelerators, other bombarding
particles have been successfully used. No attempt will be made
here to catalog the many kinds of possible transmutations, nor
will any attempt be made to discuss the theory and quantitative
data regarding nuclear reactions.
8. Induced Radioactivity
a. During the first 15 years of experimental work with nuclear
reactions, the transmutation products (insofar as could be
observed) were not radioactive.
b. However, the reactions generally were accompanied by the
emission of a charged particle and a gamma ray. These
emissions are not construed as imparting the property of
radioactivity to the target element, since they occur practically
instantaneously.
c. It was determined in 1934 that induced transmutations could
produce nuclei which were residually unstable in somewhat the
same manner as naturally occurring radionuclides.
Section 43
d. Irene Curie and Frederic Joliot reported that certain light
elements (boron, magnesium, aluminum), when bombarded with
alpha particles, continued to emit radiation for a finite time after
bombardment had stopped.
1) The following reaction, involving aluminum bombarded
with alpha particles, was the first reported instance of
induced or artificial radioactivity:
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2) The resultant nucleus 30 P was observed to be radioactive,
15
emitting a small charged particle and reaching stability
within minutes.
e. The work of Curie and Joliot stimulated similar experiments
throughout the world. As a result, radioactive isotopes of nearly Over 1,000 unstable
every element in the Periodic Table were produced by nuclear species are
bombarding a stable isotope with charged particles, neutrons, or listed in the Chart
in certain instances photons. of the Nuclides
9. Natural vs. Artificial
a. Heavy radionuclides (natural, and artificial) generally decay by a
long series of alpha and beta emissions.
b. Lighter, artificial radionuclides, such as activation and fission
products, usually decay by beta or positron emission or by
orbital electron capture.
c. In contrast to natural radioactivity, lighter artificially-produced
radionuclides generally revert to stability in only a few decay
steps.
10. Fission Products
a. Another source of radionuclides is nuclear fission. The nuclear
fragments directly resulting from fission invariably have too
large a proportion of neutrons to protons for stability, and
consequently tend to achieve stability by beta minus emission.
b. For example, take a thermal fission of 235U:
1) The n:p ratio for stable Cesium (133Cs) is 1.4:1, whereas the
above fission product has a ratio of about 1.6:1.
2) The stable ratio for Rubidium (85Rb) is 1.3:1, while the
product above has a ratio of about 1.5:1.
3) As can be seen, the fission products in the above equation
have too many neutrons.
c. Each fission fragment initiates a radioactive series, called a
fission decay chain, involving several successive beta decay
transformations.
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d. Fission product beta emission, as with other beta emitters,
generally is accompanied by gamma emission.
i. Predicting Mode of Decay
a. Radioactive nuclides tend to decay in a way that results in a
daughter nuclide that lies closer to the line of stability.
b. Nuclides below the line of stability will usually undergo beta-
minus decay.
c. Nuclides above the line of stability will usually undergo positron
decay or electron capture.
d. Nuclides at the upper end of the line of stability will usually
undergo alpha decay.
e. Figure 2 illustrates the type of decay nuclides in different regions
will typically undergo.
E. Radioactive Families
1. The transmutations associated with naturally-occurring radionuclides
frequently yield a daughter which is also radioactive.
2. To date, about 70 different naturally occurring radionuclides have
been identified, each with its own characteristic pattern of
radioactivity.
3. Most of these yield radioactive daughters and are now known to be
intimately interrelated in radioactive series or families.
4. Three Natural Decay Series
a. It has been established that most isolated radioactive species
with Z > 82 belong to one of three independent groups or
families.
Section 44
b. Each family starts with a parent radionuclide, decaying or
transmuting into a radioactive daughter nuclide, which would
again transmute into a daughter nuclide, also radioactive, and so
on until stability is attained.
These are general
rules that have
many exceptions,
especially in the
region of heavy
nuclides.
Objective 1.06.08
See Fig. 3 -
"Natural
Decay Series"
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c. One family starts with Uranium-238 ( 238
92 U ) and is called the
Uranium series.
d. Another starts with Thorium-232 ( 232
90Th ) and is called the
Thorium series.
e.
f.
A third starts with Uranium-235 ( 235
92Th ) and is called the
Actinium series.
In each series, there is a "seesawing" in the transmutation chain
between decreasing the atomic number by two with α emission
and increasing it by one with β- emission.
The historical name
of 235U was
"Actinouranium."
Note its third
daughter.
g. Each series has an isotope of Radon [historically known as
Radon ( 222
86 Rn ), Thoron ( 222
86 Rn ), and Actinon ( 219
86 Rn )
respectively] as a member of the series. All isotopes of Radon
are radioactive and are gases at standard temperature and
pressure.
h. Each series ends in a different stable isotope of Lead ( 206
82 Pb ,
208
82 Pb , 207
82 Pb and respectively).
i. Figure 3 shows the three natural decay series.
5. Artificial Series
a. There is also a fourth series, the Neptunium series, named after
its longest-lived member.
• Actually, the neptunium series has been artificially
produced and no longer occurs in nature, but it is assumed
that it did occur in nature at one time and has become
extinct because of the relatively short half-lives involved.
b. The longest-lived radionuclide in the series is 237
93 Pb with a half-
life of 2.2E06 years.
c. Assuming the age of the earth is 2.2E09 years, this would
indicate that, from the time of creation, 237Np has undergone
1,000 half-lives decay. The fraction of a radionuclide remaining
after 1,000 half-lives would be astronomically small—in the
order of 10-300 .
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It is obvious, therefore, why it would be difficult to find traces of
neptunium and its descendants in nature.
F. Chart of the Nuclides
a. General Arrangement
a. In arranging the nuclides in chart form, the number of neutrons
(N) is plotted horizontally on the x-axis against the number of
protons (atomic number, Z) on the y-axis
b. Such a plot at once reveals the continuity in composition in
progressing from the lighter to the heavier elements. Post Chart
in classroom or provide books for students to use during
discussion.
c. The full-size Chart of the Nuclides (poster) is much easier to
follow than the Nuclides and Isotopes volume which contains all
of the material from the chart in book form. A guide for using
the chart is found in the book.
b. Specific Nuclide Representation
a. Each specific nuclide is represented in the Chart of the Nuclides
by a block.
b. The coloring and labeling of each block specifies certain
information concerning the properties of the nuclide.
c. Values for atomic number (Z) are given along the left side of the
grid, and values for number of neutrons (N) are found along the
bottom.
d. A grey block denotes a stable nuclide. A typical example is
11stable sodium (
23 Na ).
Section 45
e. Unlike sodium, most elements have more than one stable
isotope. For example, magnesium (Mg) has three stable isotopes.
Objectives 1.06.09
and 1.06.10
Refer students to
block for 23Na.
Discuss block color
and values, such as
percent abundance,
activation cross-
section and atomic
mass.
Refer students to
blocks for 24Mg,
25Mg and 26Mg.
Discuss and
compare values.
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f. A white block denotes an artificially produced radioactive
nuclide. A typical example is 59 Fe .26
g. A white block with a black triangle in the lower right hand
corner denotes an artificially produced radionuclide resulting
from slow neutron fission (fission product).
h. A grey block with a black bar across the top denotes a long-
lived, naturally- occurring radioactive isotope. 238
92 U is a good
example.
c. Depicting Nuclear Processes
a. As a result of decay, radionuclides shift from block to block
within the Chart of the Nuclides. The diagram shows the relative
locations of the products of various nuclear processes.
b. As can be seen, the relative locations (displacements) of the
primary modes of decay are:
1) Alpha (α):
down 2, left 2 ( ,
↓↓ ←← )
2) Beta (β-):
up 1, left 1 ( ↑← )
3) Positron (β+)/EC:
down 1, right 1 ( ↓→ )
c. Displacements can also occur as a result of nuclear reactions
brought about through bombarding given nuclides with various
nuclear particles or gamma photons.
d. Chart of the Nuclides Summary
a. The Chart of the Nuclides provides considerable information
about the behavior of nuclides. There is continuity in
composition of the nuclides.
Refer students to
block for 59Fe.
Discuss half-life,
emissions and
energies, etc.
Refer students to
block for 90Sr.
Discuss values.
Refer students to
block for 238U.
Discuss block
colors and values.
Refer students to
diagram in Study
Guide
These changes are
depicted in the
"Guide for using the
Chart of the
Nuclides."
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b. A line drawn through the stable nuclides forms a rather smooth
curve extending from the lower left to the upper right corner of
the Chart of the Nuclides.
c. Nuclides below this line are characterized by having an excess of
neutrons and will, in general, be beta particle emitters.
d. Nuclides above this line are characterized by having an excess of
protons and will, in general, decay by positron emission or
electron capture.
e. Nuclides lying beyond the line of stability will, in general,
demonstrate a tendency to seesaw between alpha decay and beta
decay.
f. All nuclides, if followed through their various decay schemes
will eventually end in a gray box (stable isotope).
g. The Chart presents in compact style much valuable information
concerning the properties of the nuclides. These data include for:
1) Stable nuclides
a) Relative abundance
b) Cross section for activation
2) Radioactive nuclides
a) Types of emissions
b) Energies of emissions
c) Half-life Objective 1.06.11
G. Units of Activity
1. The rate of decay of a radioactive substance constitutes the quantity
of radioactivity, or activity, in that substance.
a. The definition of activity refers to the number of transformations
(disintegrations) per unit time.
b. Since the fundamental unit of time is the second, the quantity
activity is measured in disintegrations per second, or dps.
Section 46
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Since the second is a very short time period in which to make a
measurement, activity is measured in units of disintegrations per
minutes, or dpm.
c. The SI unit of activity is the becquerel, while the historical unit
is the curie. Each will be discussed below.
2. The Curie Objective 1.06.11 a.
a. Before the large-scale production of artificial radioisotopes,
radium had become a standard of comparison for radioactivity
measurements. Originally, the unit curie applied only to radium.
1) Named for Marie Curie, it was based on the disintegrations
per second (dps) occurring in the quantity of radon gas in
equilibrium with one gram of radium.
2) If permitted to attain this equilibrium, one gram of radium
will produce about 0.66 mm3 of radon.
3) In this quantity of radon, about 37 billion atoms disintegrate
each second.
b. In 1930, the International Radium Standard Commission
extended the definition to include that quantity of any
radioactive decay product of radium which underwent the same
number of dps as one gram of radium.
• It avoided specifying the figure exactly, so for some years
the exact value of the curie varied with each successive
refinement in the measurement of the decay constant or the
atomic weight of radium.
c. In 1950, the International Joint Commission on Standards, Units,
and Constants of Radioactivity redefined the curie by accepting
37 billion dps as a curie of radioactivity regardless of its source
or characteristics.
d. Current regulations define the curie (Ci) as 3.7E10
disintegrations per second (2.22E12 dpm).
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e. Since the curie represents a very large amount of activity, often See Table 5 -
smaller, and more convenient subunits are used. "Curie Subunits"
3. The Becquerel Objective 1.06.11 b.
a. The SI derived unit of activity is the becquerel (Bq) and is that 1 dps = 1 Bq
quantity of radioactive material in which one atom is
transformed per second or undergoes one disintegration per
second (1 dps).
b. Since the becquerel is a rather small unit, metric prefixes are See Table 6 -
often applied to aid in designating larger amounts of activity. "Becquerel
Superunits"
c. The relationship between the becquerel and curie is:
1) 1Bq = 1 dps = 2.7E-11 Ci
2) 1 Ci = 3.7E10 dps = 3.7E10 Bq
4. Using unit analysis and conversion, activity measurements given in
dps, dpm or curies can be converted to becquerels.
H. Specific Activity Objective 1.06.12
1. Specific activity is defined as the activity per unit mass of a
radioactive substance.
2. Reported in units such as curies per gram (Ci/g) or becquerels per
kilogram (Bq/kg).
3. Recall that the curie originated from the number of emanations from
one gram of radium every second.
4. Thus, the activity of one gram of radium is equivalent to one curie.
This means that the specific activity of radium would be 1 Ci/g.
5. It is important, however, to note that when applied to radionuclides
other than radium, the unit curie does not make apparent what mass
of the material is required.
Since one curie of activity is 37 billion dps, the mass of the material
required to produce this number of dps will be a function of the
decay rate of the atoms of the material (i.e., the disintegration
Section 47
constant) and of the number of atoms of the material per gram (i.e.,
gram atomic mass [weight]).
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For example, a curie of pure 60Co (T½ = 5.27 years) would have a
mass less than 0.9 milligrams, whereas a curie of natural 238U (T½ =
4.5E9 years) would require over two metric tons of the metal.
6. Obviously, the shorter the half-life of a radionuclide, the greater its
specific activity.
I. The Radioactive Decay Law
1. The activity of any sample of radioactive material decreases or
decays at a fixed rate which is a characteristic of that particular
radionuclide.
2. No known physical or chemical agents (such as temperature,
pressure, dissolution, or combination) may be made to influence this
rate.
3. The rate may be characterized by observing the fraction of activity
that remains after successive time intervals.
4. For convenience we choose a fraction that is easy to work with, one-
half (½).
5. In using this fraction we can observe the decay of a radionuclide
with the passing of time. We can observe how long it takes for the
activity to be reduced to one half of the activity.
6. This time that is required for the activity present to be reduced to Objective 1.06.13
one-half we call the half-life.
7. If successive half-lives are observed, we can see a reduction each
time by a fraction of one-half, and the effect will be cumulative.
a. One half-life reduces to (½)1
b. Two half-lives reduces to ½ × ½ = (½)2 or ¼
c. Three half-lives will reduce to ½ × ½ × ½ = (½)3 or c
8. In the general case the fraction of activity remaining after any
number of half lives will be (½)n, where n is the number of half-lives
that have elapsed.
9. To put it still another way, the reduction in activity occurs at an
exponential rate, which we have expressed as the power of ½.
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10. In Figure 4 it can be seen that as time passes, radioactive decay
occurs at an exponential rate.
a. In using the half-life for our time value, we express this
exponential function as (½)n.
b. Beginning at the instant chosen as the starting point we have
100% of the activity, since no time has elapsed, and the number
of half-lives is zero (n = 0).
c. If we use t to represent time, at this point, then, t = 0.
11. If we let T½ represent the half-life, then, after one half-life, t = T½,
and n = 1. This demonstrates that n represents the ratio of time
versus the half-life.
12. Mathematically, this is expressed as:
13. Obviously, the units of t must be the same as the time units of T½ in
order to determine the value of n.
a. For example, if the half-life of a certain radionuclide is 10 hours,
and we allow 4 hours to elapse, the number of half-lives would
be 4/10 = 0.4, or 0.4 half-lives.
b. The fraction remaining at that instant where t = 4 hours would
be:
14. The activity at the instant where t = 0 is the initial or original
activity, represented as A0.
15. The activity at any time t after 0 we will denote as At.
See Fig. 4 -
"Radioactive
Decay (Linear
Scale)"
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16. The value of At at any time t will be the fraction remaining times A0.
The fraction remaining is determined from the number of half-lives
that have passed.
Section 48
17. Using a proportion we can see the relationship between the two
activities:
18. By cross-multiplying we obtain the equation for determining the
remaining activity:
At = A0(½)n
For example, if the initial activity of the radionuclide mentioned
above was 52 µCi, then the activity after 4 hours would be:
19. Remember that we stated earlier that radioactive decay is an
exponential process. Recall also that a logarithm is, by definition, an
exponent.
20. If we were to plot the activity on a logarithmic scale against the time
on a linear scale, the resulting curve should be a straight line.
21. This graph shows us that the rate of decay does in fact occur at a
constant rate.
22. As time elapses from the starting instant, the activity is reduced
thereafter at the constant rate of disintegration for the particular
radionuclide involved, which we represent by the Greek letter λ
(pronounced "lambda").
23. In FIGURE 5 the reduction of activity is now a logarithmic
(exponential) function of (½)n .
A useful "rule of
thumb" to
remember is that
seven half-lives will
reduce any activity
to less than 1
percent of its
original value.
See Fig. 5 -
"Radioactive
Decay (Semi-log
Scale)"
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24. Since n is the ratio of t versus T½, the fraction remaining after time t
will be less than 1, resulting in a negative natural-logarithmic value
(ln ½ = -ln 2 = -0.693).
25. The fraction remaining will be a function of the decay constant (λ)
and the time (t).
26. If we then relate the decay constant to the half-life, λ will be a
composite of the natural log of 2 and the half-life.
27. Since the process leads to a decrease in activity, the exponent will be
represented by -λt.
28. Therefore, the decay constant itself will represent:
29. Thus, the decay constant is the fraction that disintegrates per unit
time (reciprocal time).
• If, for example, the half-life is in seconds, λ will be in sec-1.
30. The equation for activity using the decay constant will be:
a. Note that in this equation the base of the natural log is raised to a
power which includes the -ln 2.
b. The result of this equation is exactly the same at that which
results from the equation using (½)n .
c. It is simply a different way of expressing the decrease in activity
with the passage of time as a result of radioactive decay.
31. Using the data in the prior example, the equation would be:
Using calculus, the
natural logarithm
(ln) resulted from
the integration of
the first equation
devised by
Rutherford.
Objective 1.06.14
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Module 1.06 Radioactivity and Radioactive Decay Instructor’s Guide
32. Example: Given 10 mCi of 32P, which has a half-life of 14.2 days, Work example
find the quantity remaining after 60 days. problem with
students.
33. By algebraic manipulation other variables in this equation can be
solved for if the other values are known.
Have students work
practice problems in
• One example would be calculating the original activity based on Study Guide.
the current activity, decay constant and elapsed time.
J. Series Decay
1. Concerns the mathematical relationship of quantities of activity
present when two or more radionuclides exist in a decay chain.
2. Examples of a decay chain are the natural decay series, or a two-step
fission product decay series such as:
Sr90 → β- + Y90 → β-+ Zr90 (stable)
Section 49
3. The relationship between three or more radionuclides is described by
Bateman. The solution, while straight forward, is quite involved. A
two-step relationship (parent-daughter) can be readily derived and is
reasonably easy to work with.
K. Parent-daughter Relationships
1. In a radioactive decay series, the decay of the parent nuclide
produces a daughter product and radiation is emitted.
2. The daughter nuclide also produces radioactivity when it decays, as
does each successive daughter in the chain until stability is reached,
resulting in total collective activity.
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Module 1.06 Radioactivity and Radioactive Decay Instructor’s Guide
3. The activity contributed from the parent versus the daughters will
vary depending on the half-life of the parent and the half-lives of the
daughters.
4. When