Astronomy Ch. 3

9. The time it takes for a planet to come back to the same position relative to the Sun is called its _________ period. a. synodic b. sidereal c. heliocentric d. geocentric e. prograde

A

15. When the geocentric model of the solar system did not match the observed positions of the planets, a. Tycho Brahe made measurements of higher accuracy and showed the geocentric model was correct. b. Ptolemy added epicycles to the geocentric model to match the observed data. c. Galileo argued that the Sun revolved around Earth. d. Kepler was inspired to create the theory of gravity. e. Copernicus proposed the heliocentric mode.

B

4. Who of the following was not a proponent of the heliocentric model of the solar system? a. Galileo b. Copernicus c. Newton d. Ptolemy e. Aristarchus

D

43. Newton's first law states that objects in motion a. eventually come to rest. b. experience an unbalanced force. c. experience a nonzero acceleration. d. stay in motion unless acted upon by an unbalanced force. e. must be subject to zero friction.

D

47. As a car drives around a corner at constant speed, the car is a. not accelerating. b. accelerating because speed is decreasing. c. accelerating because speed is increasing. d. accelerating because the direction is changing.

D

8. Astronomers argued that the heliocentric model of the Solar System was simpler than the geocentric model, based on a. the observation that the planets do not move relative to the background stars. b. the fact that the Moon orbits Earth. c. the fact that the Sun is more massive than Earth. d. the observed retrograde motions of the planets. e. the observed timing of lunar and solar eclipses.

D

14. Which of the following are superior planets? a. Mars b. Earth and Venus c. Venus, Mars, Jupiter, and Saturn d. Earth, Jupiter, and Saturn e. Mars, Jupiter, and Saturn

E

28. Which of the following is true about a comet that is on an elliptical orbit around the Sun? a. The comet's speed is greatest when it is farthest from the Sun. b. The comet's speed is greatest when it is nearest the Sun. c. This comet's speed is zero. d. The comet's speed is constant because its mass and the Sun's mass stay approximately the same. e. The eccentricity is very low.

B

34. According to Kepler's laws, a comet with a highly eccentric orbit will a. spend most of its time near the Sun. b. spend most of its time far from the Sun. c. always be the same distance from the Sun. d. spend the same amount of time everywhere.

B

5. The amount of time a planet takes to orbit the Sun is called its _________ period. a. synodic b. sidereal c. prograde d. retrograde e. geocentric

B

20. In the ________ model of the Solar System, ________ motion is only an apparent, not a real, motion. a. geocentric; retrograde b. heliocentric; retrograde c. geocentric; prograde d. heliocentric; prograde e. Galilean; prograde

B

27. Kepler's second law says that if a planet is in an elliptical orbit around a star, then the planet moves fastest when the planet is a. farthest from the star. b. closest to the star. c. exceeding the escape velocity. d. experiencing zero acceleration. e. located at one of the foci.

B

21. _________ was the first person to introduce a mathematical heliocentric model of the Solar System from which accurate predictions could be made of planets' positions. a. Nicolaus Copernicus b. Tycho Brahe c. Johannes Kepler d. Galileo Galilei e. Isaac Newton

A

23. The time it takes a planet to complete one full orbital revolution is commonly known as its a. period. b. frequency. c. orbital domain. d. velocity. e. eccentricity.

A

36. The eccentricity of the majority of the planetary orbits in our Solar System is approximately a. 0. b. 1. c. 0.5. d. 0.2. e. infinity.

A

45. Which laws have a theoretical framework behind them? a. physical laws b. deductive laws c. empirical laws

A

52. The natural tendency of an object to resist changes in motion is called a. inertia. b. weight. c. acceleration. d. mass. e. velocity.

A

6. When Earth catches up to a slower moving outer planet and passes it like a faster runner overtaking a slower runner in an outside lane, the planet a. exhibits retrograde motion. b. slows down because it feels Earth's gravitational pull. c. decreases in brightness as it passes through Earth's shadow. d. moves into a more elliptical orbit e. exhibits prograde motion.

A

7. Observations of what astronomical events allowed astronomers to definitively determine that the heliocentric model of the solar system was correct? a. total eclipses of the Sun b. the precise motions of planets across the celestial sphere c. motion of bright stars on the celestial sphere d. the timing of the equinoxes e. the timing of the solstices

B

1. At the center of the geocentric model of the Solar System is the a. Sun. b. Moon. c. Earth. d. Venus. e. Jupiter.

C

12. Based on his observations of the planets, Copernicus calculated the relative distance of the planets from the Sun using the heliocentric model, and these distances were a. 10 times too large. b. exactly correct. c. close to the correct values, with errors less than 0.5 astronomical unit (AU). d. accurate, but not as accurate as Ptolemy's values. e. two times too small.

C

13. Which of the following are the inferior planets? a. Only Mercury b. Mercury and Mars c. Mercury and Venus d. Mars e. Mercury, Mars, and Pluto

C

2. An inferior planet is one that is a. smaller than Earth. b. larger than Earth. c. closer to the Sun than Earth. d. farther from the Sun than Earth. e. made of lighter materials than Earth.

C

30. Kepler's third law for our Solar System can be expressed mathematically as a. P ∝ A. b. P2 ∝ A2. c. P2 ∝ A3. d. P3 ∝ A2. e. P ∝ A2.

C

38. The fact that Kepler's heliocentric model of the Solar System predicted _________ more easily and accurately than the geocentric model is an illustration of how scientific theories evolve by the scientific method. a. solar eclipses b. lunar eclipses c. retrograde motion of planets d. prograde motion of planets e. the duration of the seasons

C

40. Galileo's telescopic observations of the _________ led him to conclude that the heliocentric model of the Solar System was correct. a. motion of Jupiter and Saturn b. motion of Venus c. moons of Jupiter and phases of Venus d. phases of the Moon e. epicycles of Mars

C

42. A 100-kg astronaut throws a 1-kg wrench with a force of 1 N. What is the acceleration of the wrench after the wrench leaves the astronaut's hand? a. More information is needed. b. 1 m/s2 c. Zero d. 0.01 m/s2

C

46. An inertial frame of reference is a. an object's mass. b. any moving frame of reference. c. any frame of reference moving in a straight line at a constant velocity. d. both B and C

C

53. Which of the following is a valid action-reaction force pair? a. weight force pushing down on a chair, and the chair's normal force pushing back up b. weight force on a falling object, and the drag force pulling up c. Earth pulling on the Moon, and the Moon pulling on Earth d. you pushing on a box, and the box moving

C

10. Retrograde motion is seen when ____________ due to Earth's motion. a. stars change their position in the sky with respect to background stars b. stars rise in the west and set in the east c. planets rise in the west and set in the east d. planets change the direction in which they move across the night sky e. planets orbit the Sun in the opposite direction

D

11. How did Ptolemy "fix" the geocentric system? a. He introduced retrograde motion. b. He introduced prograde motion. c. He moved the Sun to the center. d. He introduced epicycles. e. He introduced Earth's motion.

D

24. If the Sun is located at one focus of Earth's elliptical orbit, what is at the other focus? a. Earth b. the Moon c. another planet d. nothing e. Jupiter

D

29. During a certain comet's orbit around the Sun, its closest distance to the Sun is 0.6 AU, and its farthest distance from the Sun is 35 AU. At what distance will the comet's orbital velocity be the largest? a. 35 AU b. 17.8 AU c. 1.2 AU d. 0.6 AU e. The comet's velocity is constant no matter what its distance is.

D

3. A superior planet is one that is a. smaller than Earth. b. larger than Earth. c. closer to the Sun than Earth. d. farther from the Sun than Earth. e. made of heavier materials than Earth.

D

31. Kepler's third law is a relationship between an orbiting object's a. gravitational force and mass. b. acceleration and mass. c. velocity and period. d. period and semimajor axis. e. semimajor axis and velocity.

D

32. Which equation represents the relationship of the planet's period to its semimajor axis in data shown in the figure below? a. P ∝ A b. P2 ∝ A2 c. P3 ∝ A2 d. P2 ∝ A3 e. P ∝ A3

D

33. The distance between the foci when the eccentricity equals zero is a. equal to the semimajor axis. b. equal to the semiminor axis. c. half the semimajor axis. d. zero.

D

35. The average distance between a planet and the Sun is given by the _________ of its elliptical orbit. a. radius b. semiminor axis c. eccentricity d. semimajor axis e. distance between the foci

D

37. An empirical science is one that is based on a. assumptions. b. calculus. c. computer models. d. observed data. e. hypotheses.

D

39. A circular orbit has an eccentricity of _________ and a very elliptical orbit has an eccentricity of _________. a. 1; 0 b. 1; 1 c. 0; infinity d. 0; 1 e. infinity; 0

D

19. When the Sun, Earth, and a planet all lie along a straight line, the planet is at a. quadrature. b. opposition. c. only greatest elongation. d. only conjunction. e. either opposition or conjunction.

E

22. Which laws are based entirely on observational data without having any theoretical framework behind them? a. physical laws b. Galileo's laws of planetary motion c. Newton's laws of motion d. deductive laws e. empirical laws

E

41. Galileo observed what the geocentric astronomers viewed as imperfections. These observations helped Galileo to show that the heliocentric model was the more accurate model. Which was not an observation of Galileo? a. The Moon had craters. b. sunspots c. the moons of Jupiter d. Venus' phases e. the moons of Saturn

E