The present age of the Sun is about

1. The present age of the Sun is about A. 7000 years. • 100,000 years. • 5 billion years. D. 10 billion years.

2. The present age of the Sun is about A. 7000 years. • 100,000 years. • 5 billion years. • 10 billion years. Explanation: Five billion years ago, there was no Sun!

3. One astronomical unit (AU) is defined to be the distance from the Sun to A. Earth. • Jupiter. • the Kuiper Belt. D. the next nearest star.

4. One astronomical unit (AU) is defined to be the distance from the Sun to A. Earth. • Jupiter. • the Kuiper Belt. • the next nearest star.

5. Compared to the size of Earth, the Jovian planets are A. larger. • smaller. • a mixture of smaller and larger. D. more dense.

6. Compared to the size of Earth, the Jovian planets are A. larger. • smaller. • a mixture of smaller and larger. • more dense.

7. As a nebula shrinks under the influence of gravity, its rate of spin A. slows. • increases. • remains unchanged. D. turns into a protosun.

8. As a nebula shrinks under the influence of gravity, its rate of spin A. slows. • increases. • remains unchanged. • turns into a protosun. Explanation: In accord with the conservation of angular momentum, as the radius of the nebula decreases, its spin rate increases (like skaters who pulls their arms inward in a spin).

9. The energy source for the Sun or other stars is A. radiant energy. • chemical energy. • thermonuclear fusion. D. radioactivity.

10. The energy source for the Sun or other stars is A. radiant energy. • chemical energy. • thermonuclear fusion. • radioactivity.

11. Compared with the age of the Sun, the age of the universe is A. about the same. • slightly longer. • almost double. D. more than double.

12. Compared with the age of the Sun, the age of the universe is A. about the same. • slightly longer. • almost double. • more than double. Explanation: The universe is nearly 14 billion years old, more than twice the 5-billion-year age of the Sun.

13. Energy radiated by the Sun has its origin in A. decreasing mass. • increasing mass. • radioactive decay. • thermochemical reactions.

14. Energy radiated by the Sun has its origin in A. decreasing mass. • increasing mass. • radioactive decay. • thermochemical reactions. Explanation: A decrease in mass bathes the solar system with radiant energy. Solar mass is converted to energy via the celebrated equation, E = mc2.

15. The phase of matter composing the Sun is A. a tenuous solid. • a low-density liquid. • gaseous. D. plasma.

16. The phase of matter composing the Sun is A. a tenuous solid. • a low-density liquid. • gaseous. • plasma.

17. Rotation of the Sun is A. greater at the equator than in regions closer to the poles. • less at the equator than in regions closer to the poles. • in opposite directions on either side of its equator. D. a constant in the solar system.

18. Rotation of the Sun is A. greater at the equator than in regions closer to the poles. • less at the equator than in regions closer to the poles. • in opposite directions on either side of its equator. • a constant in the solar system.

19. The solar wind A. creates the tails of comets. • powers the aurora borealis on Earth. • is composed of high-speed electrons and protons. D. All of the above.

20. The solar wind A. creates the tails of comets. • powers the aurora borealis on Earth. • is composed of high-speed electrons and protons. • All of the above.

21. At eleven-year cycles, the Sun undergoes changes in A. rotational direction. • magnetic field reversal. • layer composition. D. All of the above.

22. At eleven-year cycles, the Sun undergoes changes in A. rotational direction. • magnetic field reversal. • layer composition. • All of the above. Comment: The magnetic field reversals are related to the number of sunspots.

23. Which planet has the most pronounced system of planetary rings? A. Mars. • Jupiter. • Saturn. D. Uranus.

24. Which planet has the most pronounced system of planetary rings? A. Mars. • Jupiter. • Saturn. • Uranus.

25. Which of these planets has a system of planetary rings? A. Neptune. • Uranus. • Both of the above. D. Neither of the above.

26. Which of these planets has a system of planetary rings? A. Neptune. • Uranus. • Both of the above. • Neither of the above.

27. Comets are composed mostly of A. iron. • ice and rock. • hydrogen and helium. D. silicon.

28. Comets are composed mostly of A. iron. • ice and rock. • hydrogen and helium. • silicon.

29. Which of these makes contact with Earth’s surface? A. Meteor. • Meteorite. • Meteoroid. D. None of the above.

30. Which of these makes contact with Earth’s surface? A. Meteor. • Meteorite. • Meteoroid. • None of the above. Comment: Are you comfortable with distinguishing between meteors, meteorites, and meteoroids? :-)

31. The planet with the lowest density is A. Mars. • Neptune. • Saturn. D. None of the above.

32. The planet with the lowest density is A. Mars. • Neptune. • Saturn. • None of the above. Comment: It is said that Saturn could float in a giant bathtub, because the density of Saturn is less than the density of water.

33. Which was known first, Neptune or Uranus? A. Neptune. • Uranus. • Both were known since antiquity. D. Actually, they both were discovered in the same year.

34. Which was known first, Neptune or Uranus? A. Neptune. • Uranus. • Both were known since antiquity. • Actually, they both were discovered in the same year. Explanation: Recall that perturbations in Uranus led to the discovery of Neptune, and later, Pluto.

35. Which of these planets has one or more moons? A. Earth. • Jupiter. • Uranus. D. All of the above.

36. Conceptual Physical Science 4e —Chapter 26 Which of these planets has one or more moons? A. Earth. • Jupiter. • Uranus. • All of the above.

37. Which is farthest from the Sun? A. Pluto. • Asteroid Belt. • Kuiper Belt. D. Oort Cloud.

38. Which is farthest from the Sun? A. Pluto. • Asteroid Belt. • Kuiper Belt. • Oort Cloud.

39. Pluto’s status as a major planet is controversial, because A. its orbit is highly inclined compared with those of the planets. • its composition doesn’t match any of the other planets. • it spends much of its time with comets in the Kuiper Belt. D. All of the above.

40. Pluto’s status as a major planet is controversial, because A. its orbit is highly inclined compared with those of the planets. • its composition doesn’t match any of the other planets. • it spends much of its time with comets in the Kuiper Belt. • All of the above.

41. During the time of a new Moon, A. the Sun is between Earth and the Moon. • Earth is between the Sun and Moon. • a solar eclipse is possible. D. None of the above.

42. During the time of a new Moon, A. the Sun is between Earth and the Moon. • Earth is between the Sun and Moon. • a solar eclipse is possible. • None of the above. Explanation: A new Moon is in the daytime sky, between Earth and the Sun. When it is exactly between, we have a solar eclipse. A lunar eclipse, on the other hand, occurs when the Moon is full.

43. During the time of a full Moon, the A. Sun is between Earth and the Moon. • Moon is between the Sun and Earth. • Earth is between the Sun and Moon. D. None of the above.

44. During the time of a full Moon, the A. Sun is between Earth and the Moon. • Moon is between the Sun and Earth. • Earth is between the Sun and Moon. • None of the above. Explanation: A fully illuminated Moon faces Earth when Earth is between the Sun and Moon. When alignment is exact, Earth’s shadow falls on the Moon and we have a lunar eclipse. ,

45. Just before viewing a lunar eclipse, the Moon is A. full. • new. • waxing. D. waning.

46. Just before viewing a lunar eclipse, the Moon is A. full. • new. • waxing. • waning. Explanation: A lunar eclipse is a view of Earth’s shadow. So, Earth must be between the Sun and the Moon. Just before viewing a solar eclipse, the Moon is new.

47. The type of eclipse in view of half the Earth at the same time is a A. solar eclipse. • lunar eclipse. • Either of the above. D. Neither of the above.

48. The type of eclipse in view of half the Earth at the same time is a A. solar eclipse. • lunar eclipse. • Either of the above. • Neither of the above.

49. The Moon’s eroding agents have been A. wind and storms. • plentiful water in its past. • meteoroid impacts. • All of the above.

50. The Moon’s eroding agents have been A. wind and storms. • plentiful water in its past. • meteoroid impacts. • All of the above. Explanation: The Moon is too small to hold an atmosphere, so winds and storms are not part of its history. Although evidence suggest some ice at the Moon’s poles, there is no evidence of plentiful water in its history. Meteoroid impacts have not been covered, as they have on bodies having an atmosphere. The Moon wears no make-up.