Chapter 04 - Renaissance Astronomy Chapter 04 Renaissance Astronomy Multiple Choice Questions 1. Why was Tycho unwilling to accept that the stars are too far away for him to be able to detect their parallaxes? A. He thought he could measure the angular diameters of stars B. He assumed the Earth was stationary C. He knew Saturn was at the same distance as the stars D. Trick question, he could, in fact, measure stellar parallaxes Bloom's Level: Understand Section: 4.4 2. Why did Tycho Brahe reject Copernicus's model of the solar system? A. He could not detect stellar parallax B. He could not detect retrograde motion for Mars C. The ellipse had not been discovered yet D. Tycho found mistakes in Copernicus's calculations Bloom's Level: Understand Figure: 4.11 Section: 4.4 3. Which of the following best describes Tycho's model of the solar system? A. Sun orbits Earth, planets orbit Sun B. Earth orbits Sun, planets orbit Earth C. Sun and planets orbit Earth D. Planets and Earth orbit Sun Bloom's Level: Remember Figure: 4.12 Section: 4.4 4-1 Chapter 04 - Renaissance Astronomy 4. Which of the following is one of Kepler's Laws of Planetary Motion? A. The planet's distance cubed is proportional to its distance squared B. Acceleration is proportional to unbalanced force C. An object in motion remains in motion D. The parabola is a kind of conic section. Bloom's Level: Understand Section: 4.5 5. The point of closest approach of a planet to the Sun is called the A. Aphelion B. Epicycle C. Focus D. Perihelion E. Inferior conjunction Bloom's Level: Understand Figure: 4.13 Section: 4.5 6. Suppose the distance between the two foci of an ellipse is much smaller than the semimajor axis of the ellipse. What can be said about the ellipse? A. A planet orbiting on that ellipse would have a short orbital period B. The eccentricity of the ellipse is nearly zero C. The ellipse is long and skinny D. The foci are located far from the semimajor axis Bloom's Level: Understand Figure: 4.13 Section: 4.5 4-2 Chapter 04 - Renaissance Astronomy 7. What object is located at one focus of the orbit of the planet Mars? A. The Sun B. The Earth C. Mars D. Jupiter Bloom's Level: Remember Figure: 4.15 Section: 4.5 8. The Sun is located at one focus of the orbit of a planet. What is located at the other focus? A. Nothing B. The Earth C. The planet itself D. One of the other planets Bloom's Level: Understand Figure: 4.15 Section: 4.5 9. According to Kepler's laws, a planet moves fastest in its orbit when it is A. Nearest the Earth in the Earth's orbital plane B. Nearest the Sun C. Midway between the foci of its orbit D. Farthest from the ecliptic Bloom's Level: Understand Figure: 4.15 Section: 4.5 4-3 Chapter 04 - Renaissance Astronomy 10. Suppose a planet has an elliptical orbit. The speed of the planet is 20 km/s when it is at its average distance from the Sun. Which of the following is most likely to be the planet's speed when it is farthest from the Sun? A. 15 km/s B. 20 km/s C. 25 km/s D. 30 km/s Bloom's Level: Analyze Figure: 4.15 Section: 4.5 11. Kepler's law of equal areas in equal times predicts that A. Planets move fastest at perihelion B. Comets are often in unbound orbits C. The sun must be at the center of the solar system D. Planets all must lie in the same orbital plane E. Planets are in noncircular orbits Bloom's Level: Analyze Figure: 4.15 Section: 4.5 12. Kepler's Second Law states that A. A planet moves more rapidly when near the Sun B. Planets close to the Sun have longer periods than those further away C. An object in motion remains in motion D. A planet's mass increases with distance from the Sun Bloom's Level: Understand Figure: 4.15 Section: 4.5 4-4 Chapter 04 - Renaissance Astronomy 13. A hypothetical planet orbits the Sun a distance of 4 AU. What is its orbital period? A. 4 years B. 8 years C. 16 years D. 64 years Bloom's Level: Apply Section: 4.5 14. Bodes's law "predicts" that there is a planet with an orbit having a semimajor axis of 77 AU. What would be the orbital period of the "predicted" planet? A. 77 years B. 676 years C. 115 years D. 5930 years Bloom's Level: Apply Section: 4.5 15. A planet has a semimajor axis of 10 astronomical units. The orbital period would be A. 1.7 years B. 5.2 years C. 9 years D. 32 years E. 100 years Bloom's Level: Apply Section: 4.5 16. Suppose there were very remote planets in the solar system, with periods of about 100,000 years. Approximately how far from the Sun would such a planet be? A. 200 astronomical units B. 2000 astronomical units C. 20,000 astronomical units D. 200,000 astronomical units Bloom's Level: Apply Section: 4.5 4-5 Chapter 04 - Renaissance Astronomy 17. If the size of the Earth's orbit were doubled, its period of revolution about the Sun would A. Increase about 3 times B. Stay the same C. Decrease about 3 times D. Increase about 8 times Bloom's Level: Apply Section: 4.5 18. An asteroid has an orbital period of 5 years. Approximately what is its average distance from the sun? A. 2 AU B. 3 AU C. 4 AU D. 5 AU Bloom's Level: Apply Section: 4.5 19. Callisto is 1.76 times as far from Jupiter as is Ganymede. The orbital period of Callisto is 16.7 days. What is the orbital period of Ganymede? A. About 3 days B. About 7 days C. About 10 days D. About 13 days Bloom's Level: Apply Section: 4.5 20. What is the orbital period of an asteroid that has a semimajor axis of 2.8 AU? A. 2.8 years B. 4.7 years C. 7.8 years D. 10.4 years Bloom's Level: Apply Section: 4.5 4-6 Chapter 04 - Renaissance Astronomy 21. In which model(s) of the solar system does the Earth orbit the Sun? A. Ptolemy's model and Tycho's model B. Ptolemy's model only C. Copernicus's model only D. Tycho's model and Copernicus's model Bloom's Level: Understand Figure: 4.12 Section: 4.3 22. The reason Copernicus subscribed to the heliocentric hypothesis was that A. The observations of Venusian phases convinced him B. He knew that the planets were in elliptical orbits C. It was philosophically pleasing to him D. There was official pressure to espouse a heliocentric theory Bloom's Level: Understand Section: 4.3 23. When does retrograde motion of Venus occur in the heliocentric model of the solar system? A. When Venus passes the Earth B. When the Earth and Venus are on opposite sides of the Sun C. When the Earth is nearest the Sun D. When the Sun and Venus are opposite each other in the sky Bloom's Level: Analyze Figure: 4.19 Section: 4.6 24. In the heliocentric model of the solar system, retrograde motion occurs when A. Two planets are farthest apart B. Two planets are on opposite sides of the Sun C. Two planets pass each other in their orbits D. One of the planets is nearest the Sun in its orbit Bloom's Level: Understand Figure: 4.4 Section: 4.3 4-7 Chapter 04 - Renaissance Astronomy 25. A shift in the direction of an object caused by a change in the position of an observer is called A. Parallax B. Precession C. The Coriolis effect D. Epicycle motion Bloom's Level: Understand Figure: 4.11 Section: 4.4 26. Two planets have orbital periods of 3 years and 4 years, respectively. What is the synodic period of the two planets? A. 12 years B. 1.33 years C. 1 year D. 7 years Bloom's Level: Apply Figure: 4.6 Section: 4.3 27. A planet has a synodic period of 2 years when observed from Earth. What is the sidereal (orbital) period of the planet? A. ½ year B. 1 year C. 2 years D. 2.5 years Bloom's Level: Apply Figure: 4.6 Section: 4.3 4-8 Chapter 04 - Renaissance Astronomy 28. Suppose planet X has a circular orbit. As viewed from the Earth, the maximum angle between planet X and the Sun is 65 degrees. What is the orbital distance of planet X? A. 0.9 AU B. 1.4 AU C. 1.8 AU D. 2.5 AU Bloom's Level: Create Figure: 4.7 Section: 4.3 29. Which of the following planets, when viewed from the Earth, can be seen at crescent phase? A. Mercury B. Mars C. Saturn D. Pluto Bloom's Level: Understand Figure: 4.19 Section: 4.6 30. In which model(s) of the solar system does Venus show a full range of phases from new to full? A. Both the geocentric and heliocentric B. Neither the geocentric nor heliocentric C. Geocentric D. Heliocentric Bloom's Level: Analyze Figure: 4.19 Section: 4.6 4-9 Chapter 04 - Renaissance Astronomy 31. What was significant about Galileo's discovery of Jupiter's four brightest satellites? A. It showed that theories that a planet can only have one satellite are wrong B. It showed that there are some objects that do not orbit the earth C. It showed that some satellites have atmospheres D. It showed that Jupiter is the most massive planet Bloom's Level: Understand Section: 4.6 32. Which of the following did Galileo use to support the heliocentric hypothesis? A. Prograde motion of the planets B. Phases of the Moon C. Phases of Venus D. Existence of sunspots Bloom's Level: Understand Figure: 4.19 Section: 4.6 33. Jupiter is about 5 AU from the Sun. What is its orbital period? A. 4 years B. 8 years C. 12 years D. 16 years Bloom's Level: Apply Section: 4.5 34. Kepler's Third Law can be described in what way? A. Closer planets take longer to orbit the Sun than planets that are farther away from the Sun. B. Planets that are farther away from the Sun take less time to orbit the sun than less massive planets, but more time that more massive planets. C. Planet that are farther away from the Sun take longer to orbit the Sun than planets that are closer to the Sun. D. The planet's distance from the Sun is independent of its orbital period. Bloom's Level: Understand Section: 4.3 4-10