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35.

(a) When θ is measured in radians, it is equal to the arclength divided by the radius. For very large

radius circles and small values of θ, such as we deal with in this problem,
the arcs may be
approximated as
straight lines –
which

for

our

purposes

corre-

spond to the di-
ameters d and
D of the Moon
and Sun, respec-
tively. Thus,

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D

d

R

Sun

R

Moon

θ

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θ =

d

R

Moon

=

D

R

Sun

=

⇒

R

Sun

R

Moon

=

D

d

which yields D/d = 400.

(b) Various geometric formulas are given in Appendix E. Using r

s

and r

m

for the radius of the Sun and

Moon, respectively (noting that their ratio is the same as D/d), then the Sun’s volume divided by
that of the Moon is

4
3

πr

3

s

4
3

πr

3

m

=

r

s

r

m

3

= 400

3

= 6.4

× 10

7

.

(c) The angle should turn out to be roughly 0.009 rad (or about half a degree). Putting this into the

equation above, we get

d = θR

Moon

= (0.009)

3.8

× 10

5

≈ 3.4 × 10

3

km .

Document Outline

Main Menu
Chapter 1 Measurement
- 1.1 - 1.10
  - 1.1
  - 1.2
  - 1.3
  - 1.4
  - 1.5
  - 1.6
  - 1.7
  - 1.8
  - 1.9
  - 1.10
- 1.11 - 1.20
  - 1.11
  - 1.12
  - 1.13
  - 1.14
  - 1.15
  - 1.16
  - 1.17
  - 1.18
  - 1.19
  - 1.20
- 1.21 - 1.30
  - 1.21
  - 1.22
  - 1.23
  - 1.24
  - 1.25
  - 1.26
  - 1.27
  - 1.28
  - 1.29
  - 1.30
- 1.31 - 1.40
  - 1.31
  - 1.32
  - 1.33
  - 1.34
  - 1.35
  - 1.36
  - 1.37
  - 1.38
  - 1.39
  - 1.40
- 1.41 - 1.44
  - 1.41
  - 1.42
  - 1.43
  - 1.44
Chapter 2 Motion Along a Straight Line
Chapter 3 Vectors
Chapter 4 Motion in Two and Three Dimensions
Chapter 5 Force and Motion I
Chapter 6 Force and Motion II
Chapter 7 Kinetic Energy and Work
Chapter 8 Potential Energy and Conservation of Energy
Chapter 9 Systems of Particles
Chapter 10 Collisions
Chapter 11 Rotation
Chapter 12 Rolling, Torque, and Angular Momentum
Chapter 13 Equilibrium and Elasticity
Chapter 14 Gravitation
Chapter 15 Fluids
Chapter 16 Oscillations
Chapter 17 Waves—I
Chapter 18 Waves—II
Chapter 19 Temperature, Heat, and the First Law of Thermodynamics
Chapter 20 The Kinetic Theory of Gases
Chapter 21 Entropy and the Second Law of Thermodynamics
Chapter 22 Electric Charge
Chapter 23 Electric Fields
Chapter 24 Gauss’ Law
Chapter 25 Electric Potential
Chapter 26 Capacitance
Chapter 27 Current and Resistance
Chapter 28 Circuits
Chapter 29 Magnetic Fields
Chapter 30 Magnetic Fields Due to Currents
Chapter 31 Induction and Inductance
Chapter 32 Magnetism of Matter: Maxwell’s Equation
Chapter 33 Electromagnetic Oscillations and Alternating Current
Chapter 34 Electromagnetic Waves
Chapter 35 Images
Chapter 36 Interference
Chapter 37 Diffraction
Chapter 38 Special Theory of Relativity
Chapter 39 Photons and Matter Waves
Chapter 40 More About Matter Waves
Chapter 41 All About Atoms
Chapter 42 Conduction of Electricity in Solids
Chapter 43 Nuclear Physics
Chapter 44 Energy from the Nucleus
Chapter 45 Quarks, Leptons, and the Big Bang