B.Crowell - Optics, Vol
.5.pdfPhoto Credits
All photographs are by Benjamin Crowell, except as noted below or in the captions of the photos. As noted here and in the captions, many of the photos in this chapter are from PSSC Physics, and are used under a license provided in PSSC College Physics.
Cover
Cross-section of eye: National Eye Institute, National Institutes of Health.
Chapter 4
Cross-section of eye: National Eye Institute, National Institutes of Health.
Diffraction of water wave: PSSC Physics (retouched).
Line drawing of eye: National Eye Institute, National Institutes of Health.
Chapter 5
As noted in the captions, many images in this chapter are from PSSC Physics. All the diffraction patterns in the homework problems are by the author.
Arecibo: Photos from above by Tony Acevedo, from below by David Parker. Courtesy of NAIC - Arecibo Observatory, a facility of the NSF.
Star field: Space Telescope Science Institute/Digitized Sky Survey.
© 1998 Benjamin Crowell |
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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 |
|
focal length |
m |
f |
|
magnification |
unitless |
M |
|
index of refraction |
unitless |
n |
|
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 |
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 |
Some Indices of Refraction
substance |
index of refraction |
vacuum |
1 by definition |
air |
1.0003 |
water |
1.3 |
glass |
1.5 to 1.9 |
diamond |
2.4 |
Note that all indices of refraction depend on wavelength. These values are about right for the middle of the visible spectrum (yellow).
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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