Answers are on separate web page “sample answers”
1. The term "lookback time" refers to:
A. the time at which the Big Bang occured.
B. the time required for light to travel from a distant source to an observer on Earth.
C. any point in time before the present.
D. the time required to spin around and see what is behind you.
E. the time at which some specific event occured in a distant object.
2. In the scaled-down model solar system shown in class, where the sun was represented by a basketball, where would the nearest star be located?
A. Inside the classroom
B. Near the football stadium.
C. At the corner of Hollywood & Vine.
D. Most of the way to the far side of the full-sized Earth.
E. At about the full-sized distance from Earth to Jupiter.
3. According to Newton's laws, what quantity determines the general shape of an object's orbit?
A. The total energy of the system.
B. Total mass of the system.
C. The ratio of the size of the epicycle to the size of the deferent.
D. All orbits are ellipses, and therefore have identical shapes.
E. The eclectic.
4. As viewed from the Earth, some planets appear to double back in their orbits for a while (retrograde motion). This is due to:
A. precession - the wobble of the Earth's axis of rotation.
B. the planets really do reverse their motion through space, because of outside forces.
C. the planets move on secondary orbits called epicycles, whose centers are in orbit about the Earth.
D. the fact that the Earth is not at the center of each planet's orbit.
E. none of the other answers is correct.
5. Which of the following is NOT an example of the conservation of angular momentum?
A. A student spinning on a stool pulls in his arms and speeds up.
B. A bicycle does not fall over when it is moving.
C. Newton's second law F=ma.
D. Kepler's 2nd law (planets sweep out equal areas in their orbits in equal amounts of time).
E. All of the other answers are examples of the conservation of angular momentum.
6. Which of the following statements about photons is FALSE?
A. All photons have the same energy.
B. Higher energy photons have a higher frequency.
C. A gamma-ray photon is more energetic than a visible light photon.
D. In a vacuum, photons always travel at the speed of light.
E. Photons behave like particles.
7. Which of the following passes through space the fastest?
A. Light.
B. Radio waves.
C. Infrared radiation.
D. x-rays.
E. All of these travel at the same speed.
8. How are emission lines formed?
A. An electron falls to a lower orbit (closer to the nucleus).
B. An electron jumps to a higher orbit (farther from the nucleus).
C. They are formed by black bodies.
D. They are formed when an atom is cooled down to absolute 0 (0 degrees K).
E. They do not really exist… your professor was just making it up.
9. What sort of light does the Chandra telescope measure.
A. Seismic waves.
B. Red light.
C. X-rays
D. Infrared light
E. Ultraviolet light.
10. What is one advantage of the Hubble Space Telescope over ground-based telescopes?
A. It collects more light because it has a bigger mirror.
B. Two of the other answers are correct.
C. It can detect ultraviolet light that is absorbed by the Earth's atmosphere.
D. It can detect x-ray light that is abosrbed by the Earth's atmosphere.
E. It can detect radio waves that are absorbed by the Earth's atmosphere.