```1) <1>Which of the following has your "address" in the correct order?
a) you, Earth, Local Group, Local Supercluster, solar system, Milky Way
b) you, Earth, solar system, Local Group, Milky Way, Local Supercluster
c) you, Earth, solar system, Milky Way, Local Group, Local Supercluster
d) you, Earth, solar system, Milky Way, Local Supercluster, Local Group
e) you, Earth, solar system, Local Group, Local Supercluster, Milky Way

2) <3>What does it mean when we say "angular size" of an object? Why can
we measure only angular sizes and distances for objects in the sky?

3) <2>Answer:  1. In the absence of a net force, an object moves with constant
velocity. 2. Force = rate of change in momentum or mass times acceleration.
3. For every force there is an equal and opposite reaction force.
What is the question?

4) <1>According to the universal law of gravitation, if you triple the distance
between two objects, then the gravitational force between them will
a) decrease by a factor of 6.
b) increase by a factor of 3.
c) decrease by a factor of 9.
d) increase by a factor of 9.
e) decrease by a factor of 3.

5) <1>According to the universal law of gravitation, if you double the
masses of both attracting objects, then the gravitational force between
them will  (circle the correct answer)
a) not change at all.
b) decrease by a factor of 4.
c) decrease by a factor of 2.
d) increase by a factor of 4.
e) increase by a factor of 2.

6) <2>Under what conditions is an object weightless?

7) <1>The equation F=ma, describes how much force it requires to
a) change the objects velocity within a certain time interval.
b) keep an object moving at constant speed.
c) hold an object in place.
d) have an equal but opposite reaction.

8) <2>It takes a much smaller force to push (accelerate) a gymnast off
a ledge than a huge Sumo wrestler. We can use these same physics to
explain why electrons reach the Earth before the much more massive
alpha particles (helium nuclei) after a solar flare.  Rearrange the
equation  F = ma, to solve for a,  and state why, given the same force,
electrons are accelerated more.

9) <1>When a spinning ice skater pulls in his arms, he spins faster
a) there is less friction with the air.
b) there is less friction with the ice.
c) there exists an unbalanced reaction force
d) because angular momentum is conserved.

10) <2>Examine the next figure of a low-mass star orbiting a much
higher mass star, and fill in the blanks with the correct letter:
(THE FIGURE WAS SIMILAR TO THE ONE IN THE KEPLER LAWS LAB)

a) Increasing speed: ____ to ____

b) Decreasing speed: ____ to ____

c) Smaller star has greatest speed ____

d) Smaller star has lowest speed ______

11) <3>How is a low-mass star orbiting a much higher mass star in an
eccentric orbit like a skater pulling in her arms to rotate faster?
Be specific!

12) <1>If the radius of the Sun shrunk to the size of Earth's, more than
100 times smaller, the Sun would spin
a) 100 times faster.
b) 10,000 (1002) times faster.
c) at the same rate if it has the same mass.
d) 100 times slower.
e) 10,000 (1002) times slower

13) <1>The Earth has a mass of  about 7x10^24 kg, and you have a
mass of about 60 kg.  As you sit here taking this exam, you realize that
a) you don't feel the force
b) the Earth is pulling down on you with a force that is enormous
compared to the force you are exerting on the Earth
c) there is a net force between you and the Earth
d) you are exerting an equal and opposite force on the Earth
e) gravity is always repulsive

14) <1>How are wavelength, frequency, and energy related for photons
of light?
a) Longer wavelength means higher frequency and lower energy.
b) Longer wavelength means lower frequency and higher energy.
c) Longer wavelength means higher frequency and higher energy.
d) Longer wavelength means lower frequency and lower energy.
e) There is no simple relationship because different photons travel
at different speeds.

15) <1>From shortest to longest wavelength, which of the following
correctly orders the different categories of electromagnetic radiation?
a) gamma rays, X rays, ultraviolet, visible light, infrared, radio
b) infrared, visible light, ultraviolet, X rays, gamma rays, radio
c) visible light, infrared, X rays, ultraviolet, gamma rays, radio
d) gamma rays, X rays, visible light, ultraviolet, infrared, radio
e) radio, infrared, visible light, ultraviolet, X rays, gamma rays

16) <1>From lowest energy to highest energy, which of the following
correctly orders the different categories of electromagnetic radiation?
a) gamma rays, X rays, visible light, ultraviolet, infrared, radio
b) visible light, infrared, X rays, ultraviolet, gamma rays, radio
c) radio, X rays, visible light, ultraviolet, infrared, gamma rays
d) infrared, visible light, ultraviolet, X rays, gamma rays, radio
e) radio, infrared, visible light, ultraviolet, X rays, gamma rays

17) <10>Fill in the blanks:  (frequency, energy, wavelength, speed
of light, none of these)

a) ________________________ equal to the speed of the wave divided
by the wavelength of the wave

b) ________________________ measured in cycles per second

c) ________________________ the number of peaks passing by any point each second

d) ________________________ characterizes a photon when it interacts with a light detector

e) ________________________ the distance between where the wave is emitted and
where it is absorbed
f) ________________________ measured in distance traveled over a unit of time

g) ________________________ equal to the speed of the wave divided by the wave's frequency

h) ________________________ the distance between two adjacent peaks of the wave

i) high-energy radiation has high ______________________________ as well

j) given the frequency of a photon traveling in space, you can determine its_____________________

18) <1>We can see each other in the classroom right now because we
a) emit visible light.
b) emit infrared light.