1. The visible spectrum of the Sun shows:
a) a continuous bright spectrum, crossed by many dark absorption lines.
b) a uniform continuous spectrum, with the same level of brightness at all wavelengths.
c) only a few bright emission lines.
d) only yellow light.
e) a perfect blackbody spectrum.

2. The temperature of the corona of the Sun is:
a) about 1,000,000K.
b) about the same as the photosphere, 6000K.
c) about the same as the lower chromosphere, 4500K.
d) about the same as the atmosphere of the Earth, about 300K.
e) 0K.

3. What is the strongest piece of evidence that convection occurs in the Sun?
a) the existence of absorption lines in the spectrum of the Sun.
b) the reddish color of the chromosphere of the Sun.
c) the existence of sunspots, where very strong convection is occuring.
d) the observation that the peak of the Sun's spectrum is in the visible range, not gamma rays.
e) the measurement of blueshifts and redshifts, respectively, in the bright and dark granules visible in the photosphere.

4. Sunspots:
a) are regions on the Sun with very intense magnetic fields.
b) are regions on the Sun where convection is inhibited.
c) are generally found in pairs.
d) are places where the magnetic field lines of the Sun break through the surface of the Sun.
e) all of the above.

5. Sunspots:
a) have weaker magnetic fields than the rest of the Sun.
b) are hot spots in the Sun's photosphere.
c) are regions in the sun where convection is inhibited.
d) are locations where nuclear fusion is occuring.
e) are black since they are not producing any light at all.

6. A H-alpha photon is produced:
a) during hydrogen fusion.
b) when an electron escapes from a hydrogen atom.
c) when an electron in a hydrogen atom drops from energy level 3 to energy level 2.
d) when an electron in a hydrogen atom jumps up from energy level 1 to energy level 2.
e) when an electron in a helium atom drops from energy level 3 to energy level 2.

7. An annular eclipse is:
a) An eclipse that occurs every year.
b) An eclipse of the Sun during which the photosphere is not completely blocked by the Moon.
c) An eclipse of the Sun during which only the corona is seen.
d) An eclipse of the Sun during which only the chromosphere is seen.
e) An artificial eclipse of the Sun, produced by a coronagraph.

8. Star A has a magnitude of 6, Star B has a magnitude of 5. Therefore:
a) The brightness of Star A is 10 times that of Star B.
b) The brightness of Star B is 10 times that of Star A.
c) The brightness of Star A is 2.5 times that of Star B.
d) The brightness of Star B is 2.5 times that of Star A.
e) The brightness of Star A is the same as that of Star B.

9. Sunspots are caused by:
a) Comets hitting the Sun, stirring up cooler material from under the surface.
b) Strong magnetic fields inhibiting convection.
c) The shadow of planets in front of the Sun.
d) Weaker magnetic fields than the surrounding photosphere, causing cooler gas.
e) What causes sunspots is still unknown.

10. A solar prominence is:
a) a dark spot on the photosphere of the Sun, where cool gas is sinking.
b) a large arch of gas extending above the surface of the Sun, where gas is suspended along magnetic field lines.
c) a huge explosion on the Sun, that may be caused by magnetic field lines crossing.
d) a hole in the corona, where the solar wind may escape.
e) a convective cell in the interior of the Sun.

11. Which of the following is a consequence of the solar wind?
a) the magnetic field of the Earth.
b) the Northern Lights.
c) the absorption lines in the spectrum of the Sun.
d) Neutrino oscillations.
e) The Solar Neutrino Problem.

12. The energy carried by a gamma ray photon produced in the core of the Sun reaches the Earth:
a) Immediately after the photon is produced.
b) 8.3 minutes after the photon is produced.
c) 2-3 days after the photon is produced.
d) A year after the photon is produced.
e) Many thousands of years after the photon is produced.

13. What produces a spectrum with ONLY certain color (wavelength) bright lines?
a) a low density gas.
b) a high density gas.
c) a low density gas in front of a hot dense gas.
d) a low density gas in front of a hot solid.
e) a hot solid.

14. The huge arcs of gas sometimes seen suspended for days above the Sun are:
a) solar flares.
b) mostly carbon and oxygen.
c) loops in the magnetic field lines, typically connecting sunspots.
d) generally more energetic than solar flares.
e) caused by neutrino bursts from the Sun.

15. The vapor lamps shown in class produce light at only certain specific wavelengths. This light is produced by:
a) electrons in lower energy levels of atoms jumping to higher energy levels.
b) a hot dense solid in the lamp.
c) a low density gas in front of a hot dense solid.
d) electrons in high energy levels of the atoms in the gas jumping to lower energy levels.
e) electrons escaping from atoms.

16. Why does the chromosphere of the Sun appear red?
a) It is hotter than the photosphere.
b) It is redshifted relative to the rest of the Sun.
c) It has strong H-alpha emission.
d) Nuclear reactions are occurring in the chromosphere.
e) It is mainly rusty iron.

17. Alpha Centauri A, the brightest star in the Alpha Centauri triple, has a magnitude of 0. Barnard's Star, the next closest star to us after the Alpha Centauri triple, has a magnitude of 10. Therefore:
a) Alpha Centauri A is 10 times brighter than Barnard's Star.
b) Alpha Centauri A is 100 times brighter than Barnard's Star.
c) Alpha Centauri A is 100 X 100 = 10,000 times brighter than Barnard's star.
d) Alpha Centauri A and Barnard's Star have the same brightness.
e) Barnard's Star is 10 times brighter than Alpha Centauri A.

18. An emission-line spectrum:
a) is produced by a hot solid object.
b) is sometimes called a dark line spectrum, since it looks like a continuous spectrum with dark lines across it.
c) is produced by a low density gas in front of a source of continuous light.
d) is a spectrum where light is seen at all wavelengths, except at certain specific wavelengths.
e) is a spectrum in which light is only seen at certain specific wavelengths.

19. Polaris (the North Star) is a 2nd magnitude star, while Capella (the brightest star in Auriga) has a magnitude of 0. Therefore:
a) Polaris is twice as bright as Capella.
b) Capella is twice as bright as Polaris.
c) Polaris is 2.5 X 2.5 = 6.25 times brighter than Capella.
d) Capella is 2.5 X 2.5 = 6.25 times brighter than Polaris.
e) Capella is 10 X 10 = 100 times brighter than Polaris.

20. The layer in the Sun which is the most convective is:
a) The core.
b) The layer just outside the core: between one quarter and one half of the radius.
c) The thick layer just below the photosphere.
d) The Radiative Zone.
e) There is no convection going on in the Sun.

21. From inside to out, what is the correct order of the following regions in the Sun?
a) core, radiative zone, convective zone, photosphere, chromosphere, corona.
b) core, convective zone, radiative zone, photosphere, chromosphere, corona.
c) core, radiative zone, convective zone, chromosphere, photosphere, corona.
d) core, convective zone, radiative zone, chromosphere, photosphere, corona.
e) core, radiative zone, chromosphere, convective zone, photosphere, corona.

22. How long does an individual sunspot last?
a) 5 - 10 minutes.
b) 1 - 100 days.
c) 11 years.
d) 22 years.
e) more than four hundred years. We still see the same sunspots that Galileo saw.

23. Proxima Cen, the closest star to us besides the Sun, has a magnitude of 15.5, while Lalande 21185, the 6th closest star to us, has a magnitude of 10.5. This means:
a) Proxima Cen is 5 times brighter than Lalande 21185.
b) Proxima Cen is 10 times brighter than Lalande 21185.
c) Proxima Cen is 100 times brighter than Lalande 21185.
d) Lalande 21185 is 5 times brighter than Proxima Cen.
e) Lalande 21185 is 100 times brighter than Proxima Cen.

24. An emission-line spectrum is produced by:
a) a hot dense gas.
b) a hot solid.
c) a hot low density gas.
d) a hot low density gas in front of a hot dense gas.
e) the filament in a light bulb.

25. Which of the following statements about the sunspot cycle is NOT true?
a) The number of sunspots peaks approximately every 11 years.
b) The number of neutrinos from the Sun varies with an 11-year period.
c) With each successive sunspot cycle, the magnetic polarity of the Sun changes from that of the previous cycle.
d) The sunspot cycle is a cycle of magnetic activity.
e) The number of solar flares varies with a period of about 11 years.

26. The solar wind is:
a) ultraviolet photons from the Sun.
b) visible photons from the Sun.
c) gamma ray photons from the Sun.
d) high speed charged particles streaming out from the Sun.
e) streams of high speed charged particles circulating in the interior of the Sun.

27. What is responsible for exciting molecules in our atmosphere, producing the Aurora Borealis?
a) Ultraviolet light from the Sun.
b) Visible light from the Sun.
c) Infrared light from the Sun.
d) Gamma rays from the Sun.
e) High speed charged particles from the Sun.

28. The thickness of the corona of the Sun, compared to the radius of the Sun (as measured from the center to the photosphere), is:
a) about the same size.
b) about as thick as a piece of wrapping paper, compared to the radius of a basketball.
c) about as thick as three pieces of wrapping paper, compared to the radius of a basketball.
d) about 15 times larger.
e) about a billion times larger.

29. The magnitude scale used in astronomy was invented by:
a) Galileo, in approximately 1600 A.D.
b) Albert Einstein.
c) the ancient Greek astronomer Hipparchus.
d) the scientists who built the Hubble Space Telescope.
e) the scientists who developed Charged Coupled Devices (CCDs), used to accurately measure the brightnesses of stars.

30. Which of the following can NOT be deduced from the spectrum of a star?
a) The star's radial velocity.
b) The star's chemical composition.
c) The amount of ionization of the atoms in its atmosphere.
d) The relative amount of various isotopes in its atmosphere.
e) The star's proper motion.

31. The locations of Stars X, Y, and Z are marked on the H-R diagram to the right. What types of stars are they?
a) Star X: main sequence star. Star Y: white dwarf star. Star Z: main sequence star.
b) Star X: star like the Sun. Star Y: main sequence star. Star Z: white dwarf star.
c) Star X: giant star. Star Y: main sequence star. Star Z: giant star.
d) Star X: supergiant star. Star Y: white dwarf star. Star Z: main sequence star.
e) Star X: white dwarf star. Star Y: white dwarf star. Star Z: main sequence star.

32. Stars in the lower left corner of the H-R diagram (with high temperatures and low luminosities) are called:
a) supergiant stars.
b) giant stars.
c) main sequence stars.
d) white dwarfs.
e) bright giants.

33. During a 6 month period, the apparent position of Star A changes on the sky by 0.4 arcseconds, and then shifts back again to the same location 6 months later. This means:
a) Star A has a proper motion of 0.8 arcseconds per year.
b) Star A is 1/0.4 = 2.5 parsecs away from us.
c) Star A is 1/0.8 = 1.25 parsecs away from us.
d) Star A is 1/0.2 = 5 parsecs away from us.
e) Star A is moving away from us at a rate of 8 light years per year.

34. During a 6 month period, the apparent position of Star A moved East by 0.5 arcseconds. Six months later, the apparent position had moved another 0.5 arcseconds East. Therefore:
a) Star A has a proper motion of 1 arcsecond per year.
b) Star A is 1/1 = 1 parcsec away from us.
c) Star A is 1/2 = 0.5 parsecs away from us.
d) Star A is 1/0.5 = 2 parsecs away from us.
e) Star A has a Doppler Shift of 1 arcsecond per year.

35. A parsec is:
a) the time it takes a photon of light to travel 1 A.U.
b) the time it takes a photon of light to travel a million kilometers.
c) 1/3600 of a degree.
d) the distance to the closest star.
e) the distance to a star with a parallax shift of 1 arcsecond.

36. The sunspot cycle is:
a) the time that it takes one sunspot to orbit the Sun once.
b) the total lifetime of a sunspot.
c) the time it takes a sunspot to form.
d) the time it takes a sunspot to move from the north pole of the sun to the equator.
e) the time between episodes of large numbers of sunspots.

37. Which of the following is NOT true about moving charged particles?
a) Moving charged particles are deflected by magnetic field lines.
b) Moving charged particles generate magnetic fields.
c) Moving charged particles are responsible for the magnetic field of the Earth.
d) Moving charged particles are responsible for the magnetic field of the Sun.
e) Moving charged particles travel at the speed of light.

38. The Stefan-Boltzmann Law is a relationship between:
a) the brightness of a star, its luminosity, and its distance.
b) the luminosity of a star, its radius, and its temperature.
c) the luminosity of a star, its radius, and its distance.
d) the peak of the spectrum of a star and its temperature.
e) the parallax shift and the distance.

39. The Sun is:
a) More luminous than Betelgeuse.
b) The most luminous star in the sky.
c) The hottest star in the sky.
d) The largest star in the sky.
e) hotter than Betelgeuse.

40. A third magnitude star is:
a) 10 times brighter than a second magnitude star.
b) 10 times fainter than a second magnitude star.
c) 2.5 times brighter than a second magnitude star.
d) 2.5 times fainter than a second magnitude star.
e) 100 times fainter than a second magnitude star.

41. Sunspots are:
a) sometimes associated with prominences.
b) sometimes associated with solar flares.
c) observed to have stronger magnetic fields than their surroundings.
d) cooler than the surrounding photosphere.
e) All of the above.

42. On the H-R diagram, white dwarfs are located:
a) on the lower right.
b) on the lower left.
c) on the upper right.
d) on the upper left.
e) near the middle.

43. In Astronomy, the term `proper motion' refers to:
a) the apparent `back-and-forth' motion of a star on the sky, due to the Earth's motion around the Sun.
b) the motion of a star towards us or away from us, measured by a shift in the wavelength of the light from that star.
c) the physical motion of a star through space perpendicular to our line of sight to that star.
d) a change in velocity with time.
e) the spectroscopic parallax of a star.

44. For most stars in the sky, measuring their angular size directly is impossible. However, we can determine their physical diameter indirectly if their temperature and luminosity are already known, by using:
a) their proper motion.
b) their blueshift.
c) their redshift.
d) Stefan's Law.
e) their magnitude.

45. A fifth magnitude star is:
a) 2.5 times fainter than a sixth magnitude star.
b) 2.5 times brighter than a sixth magnitude star.
c) 100 times fainter than a sixth magnitude star.
d) 100 times brighter than a sixth magnitude star.
e) 5 times brighter than a sixth magnitude star.

46. Sometimes large loops of gas are seen extending up from the photosphere of the Sun, connecting neighboring sunspots. These arcs of gas are called:
a) solar flares.
b) granules.
c) spicules.
d) dynamos.
e) prominences.

47. Which of the following components of the Sun is the hottest?
a) the photosphere.
b) the corona.
c) the chromosphere.
d) sunspots.
e) granules.

48. Approximately how long does it take the Sun to spin once on its axis? (i.e., how long does it take a sunspot to appear to orbit the Sun?)
a) 11 years.
b) 500 days.
c) 25 days.
d) 24 hours.
e) 5 minutes.

49. In the energy level diagram of hydrogen, the levels get closer and closer together as the energy increases. The red H-alpha emission line of hydrogen is produced when an electron jumps from energy level 3 to energy level 2 in a hydrogen atom, while a jump from level 4 to level 2 produces the blue-green H-beta line. What kind of photon is produced by a jump from level 2 to level 1?
a) radio.
b) IR.
c) UV.
d) microwave.
e) gamma ray.

50. True physical motion of a star through space perpendicular to our line of sight is called:
a) Rapid Walk motion.
b) Stellar parallax.
c) Proper motion.
d) Doppler shift.
e) Spectroscopic parallax.

51. A period of 11 years is:
a) Approximately the lifetime of a sunspot.
b) Approximately the lifetime of a granule on the Sun's surface.
c) Approximately the time it takes the Sun to rotate once.
d) Approximately how often the overall magnetic polarity of the Sun flips.
e) Approximately how often the overall magnetic polarity of the Earth flips.

52. Individual sunspots typically last about:
a) 5-10 minutes.
b) 1 - 100 days.
c) 6 months.
d) 11 years.
e) 26,000 years.

53. Which of the following is NOT true about prominences on the Sun?
a) they tend to be associated with sunspots.
b) they are loops of gas extending from the Sun.
c) the numbers of prominences tends to vary with an 11 year cycle.
d) they tend to follow magnetic field lines.
e) they are only seen near the north and south poles of the Sun.

54. The term `excitation', when referring to an atom, means:
a) the atom has lost an electron.
b) the atom has fused with another atom.
c) the nucleus of the atom has been split into two or more parts.
d) the atom has gained a neutron.
e) an electron in the atom has gained energy and jumped to a higher energy level.

55. The force that holds the nuclei of atoms together is:
a) the electromagnetic force.
b) the gravitational force.
c) the weak force.
d) the electroweak force.
e) the strong force.

56. To a solar astronomer, a `granule' is:
a) a sub-atomic particle produced in the core of the Sun.
b) a unit of energy equal to 4.2 joules.
c) another name for a sunspot.
d) the top of a convective cell in the Sun.
e) the angular size of the Sun, as seen from Earth.

57. The lower `atmosphere' of the Sun (i.e., just above the layer we see in visible light) is called the:
a) convective zone.
b) radiative zone.
c) corona.
d) core.
e) chromosphere.

58. The H-alpha absorption line, when measured in the laboratory, has a wavelength of 6563 Angstroms. Hydrogen is identified in the spectrum of Star A by matching the pattern of the absorption lines, however, the observed H-alpha line has a wavelength of 7000 Angstroms. This means:
a) Star A is very hot.
b) Star A is very cold.
c) Star A is moving towards us.
d) Star A is moving away from us.
e) Star A has a large parallax.

59. When is a spectrum with light at MOST wavelengths, EXCEPT a few, produced? (that is, a rainbow with a few colors missing).
a) by a hot solid.
b) by a hot dense gas.
c) by a hot low density gas.
d) by a low density gas in front of a source of continuous light.
e) by the filament in a light bulb or a burner on a stove.

60. Star A has a photospheric temperature of 5000K, while Star B's photospheric temperature is 10,000K. The wavelength of the peak of the spectrum of Star A is therefore:
a) Two times that of Star B.
b) One half that of Star B.
c) The same as that of Star B.
d) Four times that of Star B.
e) One fourth that of Star B.

61. The visible spectrum of the Sun shows:
a) a continuous bright spectrum, crossed by many dark absorption lines.
b) a uniform continuous spectrum, with the same level of brightness at all wavelengths.
c) only a few bright emission lines.
d) only yellow light.
e) a perfect blackbody spectrum.

62. The layer in the Sun which is the most convective is:
a) The core.
b) The layer just outside the core: between one quarter and one half of the radius.
c) The thick layer just below the photosphere.
d) The Radiative Zone.
e) There is no convection going on in the Sun.

63. The process of one type of neutrino converting into another is called:
a) Ionization.
b) Oscillation.
c) Excitation.
d) Fusion.
e) A random walk process.

64. The strong force is active over what distance scale?
a) the distances between stars.
b) the distances between planets in a solar system.
c) the distance between two atoms in a gas.
d) the distance between the nucleus of an atom and the electrons orbiting the atom.
e) the distances between particles in the nucleus of an atom.

65. In the energy level diagram of hydrogen, the levels get closer and closer together as the energy increases. The red H-alpha emission line of hydrogen is produced when an electron jumps from energy level 3 to energy level 2 in a hydrogen atom, while a jump from level 4 to level 2 produces the blue-green H-beta line. What kind of photon is produced by a jump from level 100 to level 99?
a) radio.
b) IR.
c) UV.
d) X-ray.
e) gamma ray.

66. Newton's first Law of Motion can be paraphrased as:
a) F = MA
b) F₁ = F₂
c) objects in motion with no forces acting on them tend to slow down and stop.
d) objects in motion keep moving with constant velocity unless acted upon by a force.
e) F = G M₁M₂/R².

67. If the mass of the Earth suddenly tripled, how would the gravitational force between the Earth and the Moon change?
a) it would increase by a factor of nine.
b) it would increase by a factor of three.
c) it would decrease by a factor of three.
d) it would decrease by a factor of nine.
e) it would stay the same.

68. Ball A has a mass of two kilograms. Ball B has a mass of four kilograms. They are hit with a bat with the same force.
a) The subsequent acceleration of Ball A is half as much as that of Ball B.
b) The subsequent acceleration of Ball A is twice as much as that of Ball B.
c) The subsequent acceleration of Ball A is four times that of Ball B.
d) The subsequent acceleration of Ball A is the same as that of Ball B.
e) The velocity of Ball A and Ball B does not change.

69. If the distance between the Earth and the Sun increased by a factor of 5, how would the gravitational force on the Earth due to the Sun change?
a) It would increase by a factor of 5.
b) It would decrease by a factor of 5.
c) It would increase by a factor of 25.
d) It would decrease by a factor of 25.
e) It would stay the same.

70. MV stars are:
a. the hottest known stars.
b. white dwarfs.
c. supergiant stars.
d. similar in temperature, luminosity, and size to our Sun.
e. fusing hydrogen to helium in their cores.

71. Stars in the lower left corner of the H-R diagram (with high temperatures and low luminosities) are called:
a) supergiant stars.
b) giant stars.
c) main sequence stars.
d) white dwarfs.
e) bright giants.

72. If the Sun were replaced by an M star with the same diameter as the Sun, but stayed at the same distance from the Earth as it is now:
a) it would be much more luminous.
b) it would be much hotter.
c) it would be much brighter.
d) it would be much fainter.
e) it would be much bluer.

73. On the H-R diagram, white dwarfs are located:
a) on the lower right.
b) on the lower left.
c) on the upper right.
d) on the upper left.
e) near the middle.

74. Most of the stars in the sky are Luminosity Class:
a) I.
b) II.
c) III.
d) IV.
e) V.

75. Our Sun is a(n):
a) MV star.
b) OI star.
c) OV star.
d) GI star.
e) GV star.

76. Which type of star has the strongest H-alpha, H-beta, and H-gamma absorption lines?
a) M.
b) O.
c) G.
d) A.
e) F.

77. A basketball and a bowling ball are both struck by a hammer with the same force. The bowling ball has a mass three times that of the basketball. Therefore:
a. The bowling ball accelerates nine times faster than the basketball.
b. The bowling ball accelerates three times faster than the basketball.
c. The basketball accelerates nine times faster than the bowling ball.
d. The basketball accelerates three times faster than the bowling ball.
e. The two balls accelerate at the same rate.

78. The mass of the Sun is 330,000 times the mass of the Earth. Therefore the gravitational force that the Sun exerts on the Earth is:
a) 330,000 times larger than the gravitational force the Earth exerts on the Sun.
b) 330,000 times smaller than the gravitational force the Earth exerts on the Sun.
c) 330,000² = 10¹¹ times larger than the gravitational force the Earth exerts on the Sun.
d) 330,000² = 10¹¹ times smaller than the gravitational force the Earth exerts on the Sun.
e) the same as the gravitational force the Earth exerts on the Sun.

79. According to Newton's first law of motion:
a) If no force acts upon a moving object, it will slow down and stop.
b) If no force acts upon a moving object, it will move in a circle.
c) If no force acts upon a moving object, it will continue moving in a straight line at a constant velocity.
d) For every action, there is an equal and opposite reaction.
e) F = MA.

80. If the distance between the Earth and the Moon suddenly doubles, the gravitational force between them:
a) doubles.
b) increases by 4 times.
c) decreases by 1/2.
d) decreases by 1/4.
e) doesn't change.

81. If the mass of the Moon suddenly doubles, but its distance from the Earth remains the same, the gravitational force between them:
a) doubles.
b) increases by 4 times.
c) decreases by 1/2.
d) decreases by 1/4.
e) doesn't change.

82. If Earth moved to be 1/4 A.U. from the Sun, how would the gravitational force on the Earth due to the Sun change?
a) It would increase by a factor of 4.
b) It would decrease by a factor of 4.
c) It would increase by a factor of 16.
d) It would decrease by a factor of 16.
e) It would stay the same.

83. Imagine you have two balls, Ball A and Ball B. Ball A has ten times the mass of Ball B. If they are hit with the same force:
a) they accelerate at the same rate.
b) Ball A accelerates ten times as fast as Ball B.
c) Ball A accelerates 100 times as fast as Ball B.
d) Ball A accelerates 1/10th as fast as Ball B.
e) Ball A accelerates 1/100th as fast as Ball B.

84. The force of gravity between two object is proportional to:
a) the difference of their masses.
b) the sum of their masses.
c) the product of their masses.
d) the reciprocal of the product of their masses.
e) only the largest of the two masses.

85. If the distance between Jupiter and its moon Europa decreases to one third of its current distance, the gravitational force between them will:
a) stay the same.
b) decrease by a factor of three.
c) decrease by a factor of nine.
d) increase by a factor of three.
e) increase by a factor of nine.

86. Sirius A has a mass that is twice as big as that of Sirius B. Therefore the gravitational force that Sirius A exerts on Sirius B is:
a) 4 times bigger than the gravitational force Sirius B exerts on Sirius A.
b) 2 times bigger than the gravitational force Sirius B exerts on Sirius A.
c) the same as the gravitational force Sirius B exerts on Sirius A.
d) one half of the gravitational force Sirius B exerts on Sirius A.
e) one quarter as big as the gravitational force Sirius B exerts on Sirius A.

87. Newton's First Law of Motion, also known as the Law of Inertia, can be paraphrased as:
a) F = MA
b) F₁ = F₂
c) objects in motion with no forces acting on them tend to slow down and stop.
d) objects in motion keep moving with constant velocity unless acted upon by a force.
e) objects in motion keep moving with constant acceleration unless acted upon by a force.

88. Which of the following is a unit of acceleration?
a) m/s.
b) m/s².
c) m/s³.
d) light years/year
e) all of the above.

89. Newton's Second Law of Motion can be paraphrased as:
a) when a force is applied to an object, the velocity of the object is proportional to its mass.
b) when a force is applied to an object, the acceleration of the object is proportional to its mass.
c) when a force is applied to an object, the velocity of the object is inversely proportional to its mass.
d) when a force is applied to an object, the acceleration of the object is inversely proportional to its mass.
e) when a force is applied to an object, the acceleration of the object is proportional to its mass squared.

90. If the distance between the Earth and the Moon decreased to half its current distance, how would the gravitational force between them change?
a) It would increase by a factor of 2.
b) It would decrease by a factor of 2.
c) It would increase by a factor of 4.
d) It would decrease by a factor of 4.
e) It would stay the same.

91. Newton's third Law of Motion can be paraphrased as:
a) F = MA
b) F₁ = F₂
c) objects in motion with no forces acting on them tend to slow down and stop.
d) objects in motion keep moving with constant velocity unless acted upon by a force.
e) F = G M₁M₂/R².

92. The tendency of an object to resist a change in its motion is called:
a) weight.
b) inertia.
c) acceleration.
d) parallax.
e) proper motion.

93. Inertia is:
a) the gravitational force on an object.
b) a change in velocity with time.
c) a change in speed with time.
d) the tendency of objects to resist changes in motion.
e) the true motion of an object in the plane of the sky.

94. If the distance between the Earth and the Moon decreased to 1/4 its current distance, how would the gravitational force on the Earth due to the Moon change?
a) It would increase by a factor of 4.
b) It would decrease by a factor of 4.
c) It would increase by a factor of 16.
d) It would decrease by a factor of 16.
e) It would stay the same.

95. The Sun has a mass 1000 times larger than the mass of Jupiter. Therefore the acceleration of the Sun due to Jupiter is:
a) 1000 times larger than the acceleration of Jupiter due to the Sun.
b) 1000² = 1,000,000 times larger than the acceleration of Jupiter due to the Sun.
c) the same as the acceleration of Jupiter due to the Sun.
d) 1/1000th of the acceleration of Jupiter due to the Sun.
e) 1/1000² = 1/1,000,000 of the acceleration of Jupiter due to the Sun.

96. Newton's Second Law of Motion tells us that the net force applied to an object equals its:
a) mass times energy.
b) momentum times velocity.
c) mass times velocity.
d) energy times acceleration.
e) mass times acceleration.

97. A 5th magnitude star is:
a) 2.5 times fainter than a fourth magnitude star.
b) 2.5 times brighter than a fourth magnitude star.
c) ten times fainter than a fourth magnitude star.
d) ten times brighter than a fourth magnitude star.
e) 100 times brighter than a fourth magnitude star.

98. The Sun is a/an:
a) A0V star.
b) M2I star.
c) M2V star.
d) G2I star.
e) G2V star.

99. A diagram of luminosity vs. temperature for stars is called a:
a) Hertz-Russell Diagram.
b) Hertz-Ronald Diagram.
c) Hertzsprung Rotation Diagram.
d) Hertzsprung-Russell Diagram.
e) Dynamic Rotation Diagram.

100. Which of the following is true about the Sun?
a) The number of sunspots on the Sun varies with a period of approximately 100 days.
b) The magnetic poles of the Sun flip approximately every 11 years.
c) Solar neutrinos have not yet been detected, but are hypothesized to exist.
d) Sunspots have much weaker magnetic fields than the rest of the photosphere.
e) It spins on its axis once every 11 years.

101. Luminosity Class III stars are classified as:
a) Supergiant stars.
b) Giant stars.
c) White dwarf stars.
d) Main sequence stars.
e) O stars.

102. According to Newton's Laws of Motion, if no force acts on a moving planet it will:
a) stop moving.
b) move in a straight line at constant speed.
c) move on a circular path at constant speed.
d) slow down.
e) speed up.

103. What is an annular eclipse?
a) When Venus passes across the face of the Sun.
b) A lunar eclipse.
c) When the Moon is directly in front of the Sun, but the angular size of the Moon is too small to block the photosphere.
d) When the Moon is directly in front of the Sun, and the angular size of the Moon is large enough to block both the photosphere and the chromosphere.
e) When the Earth is between the Sun and the Moon, so the Moon is in the Earth's shadow.

104. To a solar Astronomer, what is a butterfly diagram?
a) A plot of the rotational speed of the Sun vs. latitude on the Sun.
b) A map of the magnetic field of the Sun.
c) A plot of the latitude of sunspots on the Sun vs. time.
d) A plot of the number of solar neutrinos detected vs. time.
e) A model of convection in the interior of the Sun.

105. If the distance between the Earth and the Moon increased by a factor of 5, how would the gravitational force between them change?

a) It would stay the same.
b) It would increase by a factor of 5.
c) It would decrease by a factor of 5.
d) It would increase by a factor of 5² = 25.
e) It would decrease by a factor of 5² = 25.

106. Gas in the Corona of the Sun is:
a) Hotter and denser than that in the photosphere.
b) Colder and denser than that in the photosphere.
c) Colder and lower density than that in the photosphere.
d) Hotter and lower density than that in the photosphere.
e) About the same temperature as that in the photosphere, but lower density.

107. Which of the following is true about sunspots?
a) Sunspots tend to come in pairs, with opposite magnetic polarities.
b) Individual sunspots typically last about 11 years.
c) Individual sunspots typically last about 5 - 10 minutes.
d) Sunspots are hotter than the surrounding gas.
e) Sunspots have weak magnetic fields, compared to their surroundings.

108. Observationally, what is the difference between the spectrum of an M2V star and that of an M2I star?
a) An M2V star has a spectrum that peaks in the UV, while the spectrum of an M2I star peaks in the IR.
b) An M2V star shows strong lines of ionized helium, while a M2I star shows strong lines of titanium oxide.
c) An M2I star shows strong lines of ionized helium, while a M2V star shows strong lines of titanium oxide.
d) An M2V star has wider absorption lines, but the same lines are visible.
e) The spectral lines of a M2V star are redshifted, while the spectral lines of a M2I star are blueshifted.

109. The proper motion of a star is:
a) A back-and-forth motion of the star on the sky relative to other stars, due to the Earth's orbit around the Sun.
b) Motion of the star towards or away from us, measured by a shift in the wavelength of the star's light.
c) Motion of a star in the plane of the sky relative to other stars, due to motion of the star through space perpendicular to our line of sight.
d) The same as its spectroscopic parallax.
e) The same as its stellar parallax.

110. The absolute magnitude of a star:
a) Is lower the brighter the star is in the sky.
b) Is lower the larger the luminosity of the star.
c) Is higher the brighter the star is in the sky.
d) Is higher the larger the luminosity of the star.
e) Depends upon the distance between the observer and the star.

111. According to Newton's Third Law of Motion:
a) If no force acts upon a moving object, it will slow down and stop.
b) If no force acts upon a moving object, it will move in a circle.
c) If no force acts upon a moving object, it will continue moving in a straight line at a constant velocity.
d) F = MA.
e) For every action, there is an equal and opposite reaction.

112. If the mass of the Moon suddenly doubled, but its distance from the Earth remains the same, the gravitational force between them:
a) doubles.
b) increases by 4 times.
c) decreases by 1/2.
d) decreases by 1/4.
e) doesn't change.

113. Ionized helium lines are strongest in the spectra of:
a) A stars.
b) G stars.
c) M stars.
d) O stars.
e) K stars.

114. Which temperature star has the strongest hydrogen lines?
a) 3000K.
b) 4000K.
c) 10,000K.
d) 30,000K.
e) All stars have similar strength hydrogen lines, independent of the star's temperature.

115. A 2nd magnitude star is:
a) 2.5 X 2.5 = 6.25 times fainter than a fourth magnitude star.
b) 2.5 X 2.5 = 6.25 times brighter than a fourth magnitude star.
c) 10 times fainter than a fourth magnitude star.
d) 10 times brighter than a fourth magnitude star.
e) 10 X 10 = 100 times brighter than a fourth magnitude star.

116. alpha Centauri A is a G2V star, while alpha Centauri B is a K1V star. This means that:
a) alpha Cen A is lower luminosity and colder than alpha Cen B.
b) alpha Cen A is hotter and higher luminosity than alpha Cen B.
c) alpha Cen A is hotter but lower luminosity than alpha Cen B.
d) alpha Cen A and alpha Cen B have the same luminosity, but A is hotter.
e) alpha Cen A and alpha Cen B have the same temperature, but A is more luminous.

117. In the energy level diagram of hydrogen, the levels get closer and closer together as the energy increases. When an electron jumps from a higher level to a lower level, a photon of light is produced. Which of the following jumps for an electron in a hydrogen atom produces an ultraviolet photon?
a) Level 3 to level 2.
b) Level 100 to 99.
c) Level 4 to 3.
d) Level 4 to 2.
e) Level 2 to 1.

118. In order from hottest to coldest, what are the seven main spectral types of stars?
a) OBFGAKM
b) MKGFABO
c) MOGKFAB
d) OBAFGKM
e) ABFGKMO

119. If b is brightness, T is temperature, L is luminosity, and D is distance, what is the formula for the inverse square law of light?
a) b = L/(4*pi*D²).
b) L = b/(4*pi*D²).
c) b = D/(4*pi*L²).
d) L = D/(4*pi*T²).
e) b = L/D.

120. The period 11 years is approximately the length of time:
a) that it takes the light from the Sun to reach us.
b) that it takes the Sun to spin once on its axis.
c) that an individual granule survives on the face of the Sun.
d) that an individual sunspot survives on the face of the Sun.
e) between flips of the magnetic poles of the Sun.

121. On the x-axis of an H-R diagram, as a substitute for temperature, which of the following quantities is sometimes plotted?
a) absolute magnitude.
b) stellar radius.
c) luminosity class.
d) spectral type.
e) luminosity.

122. Sunspots:
a) Are the same thing as granules.
b) Have very strong magnetic fields, compared to the rest of the photosphere.
c) Have very strong convection, compared to the rest of the photosphere.
d) Are much hotter than the rest of the photosphere.
e) each last about 11 years before disappearing.

123. The titanium oxide lines are strongest in the spectra of:
a) M stars.
b) A stars.
c) G stars.
d) O stars.
e) K stars.

124. The stars with the largest B-V values are:
a) All very cold.
b) All very luminous.
c) All very hot.
d) All very tiny, with small radii.
e) All very huge, with huge radii.

125. Which of the following is NOT true about magnitudes?
a) A first magnitude star is 2.5 times fainter than a 2nd magnitude star.
b) The magnitude system was invented by Hipparchus.
c) The Sun has a magnitude less than 0.
d) A first magnitude star is 100 times brighter than a 6th magnitude star.
e) A fifth magnitude star is 2.5 times brighter than a 6th magnitude star.

126. Which of the following types of stars are hotter than type A stars?
a) G,K,M.
b) O,B.
c) B,F,G.
d) A stars are the hottest type of star.
e) F,G.

127. Which of the following types of stars have spectra that peak in the IR, according to Wien's Law?
a) M.
b) G.
c) B.
d) O.
e) A.

128. What do scientists call an solar eclipse in which the Moon is directly in front of the Sun, but the angular size of the Moon is too small to block the full photosphere of the Sun?
a) An alpha eclipse.
b) A spicule eclipse.
c) A granule eclipse.
d) An annular eclipse.
e) A coronal eclipse.

129. What is the equation b = L/(4*pi*D²) called?
a) Stefan's Law.
b) Wien's Law.
c) The parallax law.
d) Newton's Second Law.
e) The inverse Square Law of Light.

130. The magnetic polarity of the Sun flips approximately every:
a) six months.
b) 4.3 years.
c) 11 years.
d) 100,000 years.
e) 2 million years.

131. Supergiant stars are Luminosity Class:
a) III.
b) I.
c) V.
d) X.
e) XXX.

132. Neutrino oscillations is the theory that:
a) Neutrinos from the Sun bounce off the surface of the Earth, and don't penetrate through the surface of the Earth.
b) Neutrinos are not produced in the Sun, but only inside the interior of the Earth.
c) Neutrinos convert into visible light photons.
d) One type of neutrino turns into another type of neutrino.
e) An isolated neutrino traveling through space spontaneously converts into a neutron.

133. A plot of the latitude of the sunspots on the Sun vs. time is called a/an:
a) Hertzsprung-Russell Diagram.
b) Bumblebee Diagram.
c) Convective Diagram.
d) Butterfly Diagram.
e) Annular Diagram.

134. Spectroscopic parallax is:
a) The back-and-forth motion of a nearby star on the sky relative to other stars, due to the Earth's orbit around the Sun.
b) Motion of a star towards or away from us, measured by a shift in the wavelength of the star's light.
c) Motion of a star in the plane of the sky relative to other stars, due to motion of the star through space perpendicular to our line of sight.
d) The same thing as stellar parallax.
e) A technique of determining the distance to a star from its spectrum, using the spectral type and luminosity class to infer its luminosity and therefore its distance.

135. The spectral lines due to molecules are strongest in the spectra of:
a) M stars.
b) A stars.
c) G stars.
d) O stars.
e) K stars.

136. Spectral type A stars have stronger ____________ lines than other types of stars.
a) titanium oxide.
b) hydrogen.
c) ionized iron.
d) neutral iron.
e) ionized helium.

137. Luminosity Class III stars are called:
a) main sequence stars.
b) supergiant stars.
c) white dwarfs.
d) giant stars.
e) subgiant stars.

138. An H-alpha photon is:
a) ultraviolet.
b) red.
c) blue.
d) infrared.
e) radio.

139. The closest star to us, alpha Centauri, is actually a triplet, alpha Cen A, alpha Cen B, and Proxima Cen. Where does Proxima Centauri lie on an H-R diagram?
a) Upper left.
b) Lower left.
c) Upper right.
d) Lower right.
e) About in the middle.

140. On a Hertzsprung-Russell diagram, what two properties of stars are plotted?:
a) distance vs. velocity.
b) luminosity vs. brightness.
c) luminosity vs. temperature.
d) radius vs. mass.
e) luminosity vs. distance.

141. Most of the following are more frequently associated with sunspots than with the rest of the Sun's photosphere. What is the exception (i.e., which is NOT more frequently detected with sunspots than with their surroundings?)
a) solar neutrinos.
b) solar prominences.
c) solar flares.
d) strong magnetic fields.
e) colder gas in the photosphere than outside of the sunspot.

142. A Doppler shift is:
a) The back-and-forth shift of a star on the sky, due to the Earth's orbit around the Sun.
b) The shift in the position of a star on the sky relative to background stars, due to a true motion of the star through space.
c) For a hot solid or hot dense gas, the increase in the wavelength of the peak of the spectrum with decreasing temperature.
d) An increase in the luminosity of an object due to an increase in its temperature.
e) The shifting of the wavelength of the light seen by an observer, due to the relative motion of the observer and the source of light.

143. To an Astronomer, what does the term solar maximum refer to?
a) When the Earth is at its closest position to the Sun, so the Sun has its largest angular size.
b) When the total physical diameter of the corona of the Sun is its largest extent.
c) When the number of sunspots on the Sun reaches a maximum, in a plot of number of spots vs. time.
d) When the nuclear reactions in the core of the Sun are at at a maximum, in a plot of number of reactions vs. time.
e) When the number of neutrinos produced by the Sun reaches a maximum, in a plot of neutrino detections vs. time.

Answers: 1a, 2a, 3e, 4e, 5c, 6c, 7b, 8d, 9b, 10b, 11b, 12e, 13a, 14c, 15d, 16c, 17c, 18e, 19d, 20c, 21a, 22b, 23e, 24c, 25b, 26d, 27e, 28d, 29c, 30e, 31a, 32d, 33d, 34a, 35e, 36e, 37e, 38b, 39e, 40d, 41e, 42b, 43c, 44d, 45b, 46e, 47b, 48c, 49c, 50c, 51d, 52b, 53e, 54e, 55e, 56d, 57e, 58d, 59d, 60a, 61a, 62c, 63b, 64e, 65a, 66d, 67b, 68b, 69d, 70e, 71d, 72d, 73b, 74e, 75e, 76d, 77d, 78e, 79c, 80d, 81a, 82c, 83d, 84c, 85e, 86c, 87d, 88b, 89d, 90c, 91b, 92b, 93d, 94c, 95d, 96e, 97a, 98e, 99d, 100b, 101b, 102b, 103c, 104c, 105e, 106d, 107a, 108d, 109c, 110b, 111e, 112a, 113d, 114c, 115b, 116b, 117e, 118d, 119a, 120e, 121d, 122b, 123a, 124a, 125a, 126b, 127a, 128d, 129e, 130c, 131b, 132d, 133d, 134e, 135a, 136b, 137d, 138b, 139d, 140c, 141a, 142e, 143c.