Download Goals for today: 1. Math 2. Units

Chapter 1. Introduction
Math Review
Prefixes for units
Conversion of units
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Goals for today:
1. Math
2. Units
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Math Review: Powers and Exponents (Appendix A in textbook)
Definitions
a n  a  a  a...  a : multiply a by n times
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an  n 
a
a  a  a...  a
a0  1
Prove:
an
a a a ,
 a nm ,
m
a
(a n ) m  a nm , (ab) n  a nb n
n
m
nm
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iClicker Quiz
104  ?
(a) 10,000
(b) 6
(c) -10,000
(d) 0.0001
(e) 0.00001
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iClicker Quiz
(102 )3  ?
(a) 10-6
(b) 101
(c) 0.1
(d) -60
(e) -10
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Prefix for SI unit
3000 m = 3 x 1,000 m = 3 x 103 m = 3 km
(1000 = kilo = k)
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1,000,000,000 = 10 = giga = G
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1,000,000 = 10 = mega = M
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1,000 = 10 = kilo = k
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0.005 s = 5 x 0.001 s = 5 x (1/1000) s = 5 x 10 s = 5 ms
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0.01 = 10 = centi = c
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0.001 = 10 = mili = m
0.000 001 = 10-6 = micro =

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0.000 000 001 = 10 = nano = n
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Example
a)0.048 m
b)0.0000048 m
c) 0.00000048 m
d)0.0048 m
e)0.000000000000048 m
f) None of above
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Example of Other units and conversion of units
1 mile = 1609 m  1.6 km
1 g = 0.001 kg = 10-3 kg
1 hour = 60 min = 60 x 60 sec = 3600 s
1 L = 1 Liter = 1000 cm3 = 0.001 m3
1 cc = 1 cubic centimeter = 1 cm3
Conversion factors
 See Table A in Appendix
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Example
“Bao Xishun, a herdsman listed by the
Guinness World Records as the tallest
living man at seven-feet, nine-inches
tall, walks with his bride, Xia Shujuan,
Find the height in cm.
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Example
1 mile = 1609 m.
2000 m = ? mile
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iClicker Quiz
The area of square in m2
3 cm
is
(a ) 9 102 m 2
3 cm
(b) something else
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Hint : 0.01 = 10 = centi = c
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Significant figures
“Someone’s height is 165.2 cm.” does NOT mean
“Someone’s height is 165.200000 cm.”,
although 165.2 = 165.2000000 in math.
Addition and Subtraction
165.2 cm
+ 3.42 cm
---------------168.6 cm
Multiplication and division
11.2 cm x 6.7 cm = 75cm^2, NOT 75.04 cm^2
3 digits
2 digits
Match to lower number of digits
between the two numbers
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