B.Crowell - Electricity and Magnetism, Vol
.4.pdftransformer 135
U
Urban, Pope 23
V
volt (unit) defined 76
voltage
related to electric field 118
W
waves electromagnetic 136 gravitational 114
weak nuclear force 58, 142
Index 161
162 Index
Photo Credits
All photographs are by Benjamin Crowell, except as noted below. Credits marked with an asterisk are photographs or illustrations from the turn of the 20th century whose copyrights have expired.
Cover
Cat neuron: Courtesy of Richard J. Harris, University of Western Ontario. Accelerator: Courtesy of A. Zachau, GSI.
Chapter 1
Lightning: C. Clark/NOAA photo library, uncopyrighted. J.J. Thomson: Harper’s Monthly, 1904.* Millikan’s apparatus: Caltech.* Robert Millikan: Clark Millikan, 1891.*
Chapter 2
Curies: Harper’s Monthly, 1904.* GAMMASPHERE: C.J. Lister/R.V.F. Janssens, uncopyrighted.
Chapter 3
Knifefish: Courtesy of Greg DeGreef. Superconducting accelerator segment: Courtesy of Argonne National Laboratory, managed and operated by the University of Chicago for the U.S. Department of Energy under contract No. W-31-109-ENG-38.
Chapter 6
Radar: U.S. Forestry Service.
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Useful Data
Metric Prefixes
M- |
mega- |
106 |
|
k- |
kilo- |
103 |
|
m- |
milli- |
10 |
–3 |
μ- (Greek mu) |
micro- |
10 |
–6 |
n- |
nano- |
10 |
–9 |
p- |
pico- |
10 |
–12 |
f- |
femto- |
10 |
–15 |
(Centi-, 10-2, is used only in the centimeter.)
Notation and Units
quantity |
unit |
symbol |
|
distance |
meter, m |
x, |
x |
time |
second, s |
t, |
t |
mass |
kilogram, kg |
m |
|
density |
kg/m3 |
ρ |
|
force |
newton, 1 N=1 kg.m/s2 |
F |
|
velocity |
m/s |
v |
|
acceleration |
m/s2 |
a |
|
energy |
joule, J |
E |
|
momentum |
kg.m/s |
p |
|
angular momentum |
kg.m2/s |
L |
|
period |
s |
T |
|
wavelength |
m |
λ |
|
frequency |
s-1 or Hz |
f |
|
charge |
coulomb, C |
q |
|
current |
ampere, A |
I |
|
voltage (potential) |
volt, V |
V |
|
resistance |
ohm, Ω |
R |
|
electric field |
N/C |
E |
|
magnetic field |
tesla, 1 T=1 N.s/C.m |
B |
|
Fundamental Constants
gravitational constant |
G=6.67x10 –11 N.m2/kg2 |
|
Coulomb constant |
k=8.99x109 |
N.m2/C2 |
quantum of charge |
e=1.60x10 –19 C |
|
speed of light |
c=3.00x108 |
m/s |
magnetic field constant |
μo=4πx10–7 |
T.m/A |
Conversions |
||
Conversions between SI and other units: |
||
1 inch |
= |
2.54 cm (exactly) |
1 mile |
= |
1.61 km |
1 pound |
= |
4.45 N |
(1 kg).g |
= |
2.2 lb |
1 gallon |
= |
3.78x103 cm3 |
1 horsepower |
= |
746 W |
1 kcal* |
= |
4.18x103 J |
*When speaking of food energy, the word “Calorie” is used to mean 1 kcal, i.e. 1000 calories. In writing, the capital C may be used to indicate
1 Calorie=1000 calories.
Conversions between U.S. units:
1 foot |
= |
12 inches |
1 yard |
= |
3 feet |
1 mile |
= |
5280 ft |
Earth, Moon, and Sun
body |
mass (kg) |
radius (km)radius of orbit (km) |
|
earth |
5.97x1024 |
6.4x103 |
1.49x108 |
moon |
7.35x1022 |
1.7x103 |
3.84x105 |
sun |
1.99x1030 |
7.0x105 |
|
The radii and radii of orbits are average values. The moon orbits the earth and the earth orbits the sun.
Subatomic Particles
particle |
mass (kg) |
charge |
radius (fm) |
electron |
9.109x10-31 |
–e |
<~0.01 |
proton |
1.673x10-27 |
+e |
~1.1 |
neutron |
1.675x10-27 |
0 |
~1.1 |
neutrino |
~10 –39 kg? |
0 |
? |
The radii of protons and neutrons can only be given approximately, since they have fuzzy surfaces. For comparison, a typical atom is about a million fm in radius.
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