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2. Question 1 Mars, Jupiter, and Saturn show retrograde motion because
planets move on epicycles.
planets orbit the Sun in the same direction.
Earth moves faster in its orbit.
they are closer than Uranus.
they rotate quickly on their axes.
Answer: c
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3. Question 1 Mars, Jupiter, and Saturn show retrograde motion because
planets move on epicycles.
planets orbit the Sun in the same direction.
Earth moves faster in its orbit.
they are closer than Uranus.
they rotate quickly on their axes.
Explanation: As Earth overtakes and “passes” the outer planets, they seem to slow down and then reverse direction.
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4. Question 2
How did the geocentric model account for day and night on Earth?
The Earth rotated.
The Sun rotated.
The geocentric model couldn’t account for day and night.
The Earth revolved around the Sun.
The Sun orbited Earth.
Answer: e
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5. Question 2
How did the geocentric model account for day and night on Earth?
The Earth rotated.
The Sun rotated.
The geocentric model couldn’t account for day and night.
The Earth revolved around the Sun.
The Sun orbited Earth.
Explanation: The geocentric model held that the Earth was motionless in the center of the universe.
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6. Question 3 Epicycles were used in Ptolemy’s model to explain why
planets moved in the sky.
Earth was at the center.
retrograde motion occurred.
Earth wobbled on its axis.
inner planets were always seen near the Sun.
Answer: c
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7. Question 3 Epicycles were used in Ptolemy’s model to explain why
planets moved in the sky.
Earth was at the center.
retrograde motion occurred.
Earth wobbled on its axis.
inner planets were always seen near the Sun.
Explanation: Planets were assumed to move uniformly on an epicycle, as it moved uniformly around Earth.
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8. Question 4
The geocentric model was supported by Aristotle because of which of the following?
Stars don’t seem to show any parallax.
We don’t feel as though Earth moves.
Objects fall toward Earth, not the Sun.
We don’t see an enormous wind.
All of the above were valid reasons.
Answer: e
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9. Question 4
The geocentric model was supported by Aristotle because of which of the following?
Stars don’t seem to show any parallax.
We don’t feel as though Earth moves.
Objects fall toward Earth, not the Sun.
We don’t see an enormous wind.
All of the above were valid reasons.
Explanation: Aristotle thought that if the Earth rotated and orbited, we would feel its motion.
In Aristotle’s time, the size of the solar system and distances to stars were assumed to be much, much smaller. Parallax was expected to be seen.
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10. Question 5 The heliocentric model assumes that
planets move on epicycles.
Earth is the center of the solar system.
the stars move on the celestial sphere.
the Sun is the center of the solar system.
Earth’s axis wobbles over 26,000 years.
Answer: d
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11. Question 5 The heliocentric model assumes that
planets move on epicycles.
Earth is the center of the solar system.
the stars move on the celestial sphere.
the Sun is the center of the solar system.
Earth’s axis wobbles over 26,000 years.
Explanation: Heliocentric models proposed by Aristarchus and others were considered wrong by Aristotle and his followers.
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12. Question 6 Copernicus’s important contribution to astronomy was
proving planets move around the Sun in elliptical orbits.
the theory of gravity.
proposing a model that easily explained the retrograde motions of the planets.
discovering the Sun was not at the center of the Milky Way.
discovering the four moons of Jupiter.
Answer: c
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13. Question 6 Copernicus’s important contribution to astronomy was
proving planets move around the Sun in elliptical orbits.
the theory of gravity.
proposing a model that easily explained the retrograde motions of the planets.
discovering the Sun was not at the center of the Milky Way.
discovering the four moons of Jupiter.
Explanation: His heliocentric model easily explained retrograde motion because planets orbited the Sun at different speeds.
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14. Question 7 Copernicus’s heliocentric model was flawed because he
assumed planets moved in ellipses.
didn’t know about Uranus and Neptune.
couldn’t account for gravity.
couldn’t explain retrograde motion.
didn’t assume planets moved in ellipses.
Answer: e
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15. Question 7 Copernicus’s heliocentric model was flawed because he
assumed planets moved in ellipses.
didn’t know about Uranus and Neptune.
couldn’t account for gravity.
couldn’t explain retrograde motion.
didn’t assume planets moved in ellipses.
Explanation: Copernicus’s model still needed small epicycles to account for observed changes in planetary speeds.
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16. Question 8
Who published the first astronomical observations made with a telescope?
Hipparchus
Galileo
Tycho
Copernicus
Kepler
Answer: b
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17. Question 8
Who published the first astronomical observations made with a telescope?
Hipparchus
Galileo
Tycho
Copernicus
Kepler
Explanation: Galileo published the “Starry Messenger” in 1610, detailing his observations of the Moon, Jupiter’s moons, stars, and nebulae.
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18. Question 9
Which of Galileo’s initial observations was most challenging to established geocentric beliefs?
Craters on the Moon
Sunspots
Lunar maria
Satellites of Jupiter
Stars of the Milky Way
Answer: d
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19. Question 9
Which of Galileo’s initial observations was most challenging to established geocentric beliefs?
Craters on the Moon
Sunspots
Lunar maria
Satellites of Jupiter
Stars of the Milky Way
Explanation: Seeing four moons clearly move around Jupiter disproved that everything orbited Earth and showed Earth could orbit the Sun and not lose its moon, too.
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20. Question 10
Which hero of the Renaissance postulated three “laws” of planetary motion?
Kepler
Newton
Galileo
Tycho Brahe
Copernicus
Answer: a
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21. Question 10
Which hero of the Renaissance postulated three “laws” of planetary motion?
Kepler
Newton
Galileo
Tycho Brahe
Copernicus
Explanation: Note that Isaac Newton is also well known for three general laws of motion, but Kepler’s laws are about objects in orbits, like planets orbiting a star.
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22. Question 11 Kepler’s first law of planetary orbits states that
planets orbit the Sun.
orbits are noncircular.
orbits are elliptical in shape.
all of the above are stated.
Answer: d
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23. Question 11 Kepler’s first law of planetary orbits states that
planets orbit the Sun.
orbits are noncircular.
orbits are elliptical in shape.
all of the above are stated.
Explanation: Kepler’s laws apply to all orbiting objects. The Moon orbits Earth in an ellipse, and the Space Shuttle orbits Earth in an ellipse, too.
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24. Question 12
Earth is closer to the Sun in January. From this fact, Kepler’s second law tells us that
Earth orbits slower in January.
Earth orbits faster in January.
Earth’s orbital speed doesn’t change.
Answer: b
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25. Question 12
Earth is closer to the Sun in January. From this fact, Kepler’s second law tells us
Earth orbits slower in January.
Earth orbits faster in January.
Earth’s orbital speed doesn’t change.
Explanation: Kepler’s second law means that a planet moves faster when closer to its star.
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26. Question 13
Kepler’s third law relates a planet’s distance from the Sun and its orbital
speed.
period.
shape.
velocity.
Answer: b
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27. Question 13
Kepler’s third law relates a planet’s distance from the Sun and its orbital
speed.
period.
shape.
velocity.
Explanation: Kepler’s third law P2 = a3 means more distant planets orbit more slowly.
Venus’s period = 225 days
Venus’s axis = 0.7 AU
Earth’s period = 365 days
Earth’s axis = 1 AU
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28. Question 14
Newton’s law of gravity states that the force between two objects
increases with distance.
depends on the state of matter (solid, liquid, or gas).
can be attractive or repulsive.
increases with mass.
Answer: d
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29. Question 14
Newton’s law of gravity states that the force between two objects
increases with distance.
depends on the state of matter (solid, liquid, or gas).
can be attractive or repulsive.
increases with mass.
Explanation: The attractive force of gravity increases with greater mass, and decreases quickly with greater distance.
The force doesn’t depend on the kind of matter.
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