Name: Period: Date: Astronomy Ch 16 The Sun MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) The light we see from the Sun comes from which layer? A) troposphere B) corona C) photosphere D) ionosphere E) chromosphere 1) 2) The temperature of the layer of gas that produces the visible light of the Sun is: A) 3,500 K B) 15 million K C) 300,000 K D) 5,800 K E) 12,300 K 2) 3) Why couldn't you stand on the Sun's surface? A) You could stand on it, if a sufficiently protective spacesuit could be designed. B) The Sun doesn't have a solid surface. C) You could stand on the surface. D) The Sun's surface is too highly magnetized for anything to survive there. E) The Sun has no surface at all...the photosphere is an illusion. 3) 4) How many planet Earths could fit inside the Sun? A) almost ten million B) 110 C) about a thousand D) close to a billion E) a little over a million 4) 5) The density of the Sun is most similar to which object? A) Mercury B) the Moon C) Jupiter D) Halley's Comet's nucleus E) the Earth 5) 6) The area in the Sun's atmosphere located above the chromosphere (1500-10,000 km) where the temperature rises dramatically is called the A) solar wind. B) corona. C) transition zone. D) photosphere. E) convection zone. 6) 1
7) About what percent of the incoming energy from the Sun' reaches Earth's surface? A) 60-80% B) 50-70% C) 30-60% D) 70-90% E) 80-100% 7) 8) The solar constant is a measure of A) the total energy emitted by the Sun in all directions. B) the energy received by the Sun at any location in the solar system. C) the energy received by the Sun on Earth's surface. D) the energy received by the Sun at the location of Earth. E) the energy emitted by the Sun at the photosphere. 8) 9) The luminosity of the Sun is a measure of A) the energy emitted by the Sun at the photosphere. B) the energy received by the Sun on Earth's surface. C) the energy received by the Sun at any location in the solar system. D) the energy received by the Sun at the location of Earth. E) the total energy emitted by the Sun in all directions. 9) 10) From inside out, which is in the correct order for the structure of the Sun? A) radiative zone, convective zone, chromosphere B) photosphere, radiative zone, corona C) core, chromosphere, photosphere D) core, convective zone, radiative zone E) convective zone, radiative zone, granulation 10) 11) By what mechanism does solar energy reach the Sun's photosphere from the layer just underneath it? A) radiation B) convection C) differentiation D) conduction E) ionization 11) 12) Hydrostatic equilibrium in our Sun is the balance between A) radiation and gravitation. B) gravitation and pressure. C) convection and gravitation. D) convection and radiation. E) pressure and radiation. 12) 13) The vibrations of the Sun reveal information about A) the production of energy in the Sun. B) the interior structure of the Sun. C) the temperature of the core of the Sun. D) the structure of the atmosphere of the Sun. E) the magnetic field of the Sun. 13) 2
14) The above diagram indicates that A) the Sun is more dense at its core than at its surface. B) the Sun is most dense somewhere between its surface and its core. C) the Sun is least dense somewhere between its surface and its core. D) the Sun has about the same density throughout its interior. E) the Sun is more dense at its surface than at its core. 14) 15) The above diagram indicates that A) the Sun is hotter at its surface than at its core. B) the Sun is coolest somewhere between its surface and its core. C) the Sun has about the same temperature throughout its interior. D) the Sun is hottest somewhere between its surface and its core. E) the Sun is hotter at its core than at its surface. 15) 16) What two energy transport mechanisms, in order from outside the core to the surface, is found in the Sun? A) conduction, radiative diffusion B) radiative diffusion, convection C) conduction, convection D) radiative diffusion, conduction E) convection, conduction 16) 3
17) What is the size of a typical granule or convection cell seen in the photosphere? A) 10 km B) 1,000 km C) 100 km D) 1 km E) 10,000 km 17) 18) The pattern of rising hot gas cells all over the photosphere is called: A) convective projections. B) sunspots. C) prominences. D) filaments. E) granulation. 18) 19) The outward pressure of hot gas in the Sun A) weakens the magnetic field. B) is increasing the Sun's diameter. C) is cooling the photosphere. D) is balanced by the inward gravitational pressure. E) is responsible for variations in the sunspot cycle. 19) 20) When the chromosphere can be seen during a solar eclipse, it appears: A) invisible. B) red. C) blue. D) yellow. E) violet. 20) 21) From where does most of the solar wind flow? A) sunspots B) coronal holes C) granules D) prominences E) flares 21) 22) What is it about the Sun's corona that astronomers don't understand? A) The Sun's corona extends to the outer reaches of the solar system. B) The corona seems to absorb 2/3 of the neutrinos that pass thorough it. C) The corona is much hotter than layers of the Sun that are closer to the solar interior. D) No one knows why that part of the Sun's atmosphere does not drift away into space. E) During total solar eclipses, the corona sometimes disappears from view. 22) 23) When we glimpse the chromosphere at the start and end of totality, its color is A) green (the famous flash). B) blue, due to the ionization of nitrogen by the magnetic fields. C) yellow, like the photosphere below it. D) white from the moonlight. E) red, due to ionized hydrogen at lower pressure. 23) 4
24) The percentage (by mass) of the Sun that is Hydrogen is about A) 9% B) 71% C) 27% D) 91% E) less than 1% 24) 25) The percentage (by number of atoms) of the Sun that is Hydrogen is about A) 71% B) less than 1% C) 9% D) 91% E) 27% 25) 26) The percentage (by mass) of the Sun that is Helium is about A) 91% B) less than 1% C) 71% D) 9% E) 27% 26) 27) A loop of gas following the magnetic field lines between sunspots' poles is A) a prominence. B) a coronal mass ejection. C) a flare. D) a coronal hole. E) a ray. 27) 28) How long does the sunspot cycle last, on average? A) about 11 years B) about 76 years C) between 25 and 35 days D) 365.25 days E) about seven years 28) 29) Visible sunspots lie in the A) chromosphere. B) radiative zone. C) granulation in the photosphere. D) corona. E) transition zone. 29) 30) As the Sun rotates, an individual sunspot can be tracked across its face. From eastern to western limb, this takes about A) 12 hours. B) a week. C) two weeks. D) a month. E) 5.5 years. 30) 5
31) The most striking example of solar variability was the A) Maunder Minimum from 1645-1715. B) Dust Bowl drought of the 1930s. C) the fall of Rome. D) Joseph's seven lean years in the Old Testament. E) Sporer Minimum that doomed the Anasazi. 31) 32) Sunspots A) were most numerous during the Maunder Minimum. B) are always found close to the Sun's poles. C) are relatively constant in number every year. D) come in pairs, representing the north and south magnetic fields. E) travel over the surface of the Sun from pole to pole. 32) 33) Sunspots are dark splotches on the Sun. Which statement is true? A) They are extremely hot, but cooler than the surrounding areas of the Sun. B) They are hotter than the surrounding areas of the Sun. C) They are solid bodies floating on the surface of the Sun. D) They are associated with areas of very low magnetic fields. E) They are extremely cold objects, as cold as Pluto. 33) 34) How would sunspots appear if you could magically remove them from the Sun? A) Because sunspots are dark spots, they would be invisible against the blackness of space. B) They would shine only with reflected sunlight, appearing similar to Venus. C) They would appear blue-white, like Sirius but brighter. D) They would not appear any differently than on the surface of the Sun. E) They would shine bright orange in color, like Arcturus. 34) 35) While observing the Sun, you note a large number of sunspots. What can you conclude? A) Earth's climate will be unusually cold. B) The Sun's rotation is slower than average. C) There are likely to be an above average number of flares and prominences. D) The Sun is less luminous than usual. E) This is a period of low solar activity. 35) 36) The numbers of sunspots and their activity peak about every: A) year. B) 76 years. C) 36 days. D) eleven years. E) six months. 36) 37) Loops of glowing hydrogen seen hanging over the solar limb during totality are: A) haloes. B) filaments. C) solar rainbows. D) prominences. E) flares. 37) 6
38) During a period of high solar activity, the corona A) disappears. B) is more irregular. C) shrinks to half its normal size. D) becomes smooth and even. E) cools almost to the temperature of the photosphere. 38) 39) The solar winds blow outward from A) coronal holes. B) sunspots. C) the entire photosphere. D) the Sun's poles only. E) flares. 39) 40) Which of these are not associated with the active Sun? A) flares B) aurora C) prominences D) sunspots E) granulation 40) 41) Suppose a large flare is detected optically. How long until radio interference arrives? A) 8.5 minutes later B) simultaneously C) no relation between the two D) about four days E) about 12 hours 41) 42) Which of the following is NOT a property of neutrinos? A) can change forms in the eight minutes from the Sun's core to us B) cannot interact at all with normal matter C) neutral in charge D) can travel very close to the speed of light E) almost massless 42) 43) The critical temperature the core must reach for a star to shine by fusion is A) 5,800 K. B) 11,000 K. C) 127,000 K. D) 10 million K. E) 100 million K. 43) 44) In the proton-proton cycle, the helium atom and neutrino have less mass than the original hydrogen. What happens to the "lost" mass? A) It is ejected into space. B) It is recycled back into hydrogen. C) It is transformed into electrons. D) It is converted to energy. E) Conservation of mass dictates no mass can be lost. 44) 7
45) The primary source of the Sun's energy is A) the weak force creating energy from uranium decay. B) oxidation of carbon in the core. C) the strong force fusing hydrogen into helium. D) dark energy. E) gravitational collapse of the helium coreward. 45) 46) In the proton-proton cycle, the positron is A) massless. B) a spin conservation particle. C) intermediate between the proton and neutron in mass. D) an anti-electron. E) the chief means energy reaches the photosphere. 46) 47) What natural barrier tries to prevent two protons from combining? A) antigravity B) the weak nuclear force C) dark energy D) electromagnetic repulsion E) the strong nuclear force 47) 48) The critical temperature to initiate the proton-proton cycle in the cores of stars is: A) 10 million K. B) 2,300,000 K. C) 100 million K. D) 3,000 K. E) 5,800 K. 48) 49) Which is the net result of the proton-proton chain? A) 4 protons = 2 helium 2 + 2 positrons + ultraviolet radiation B) 2 protons = deuterium + a positron + an antineutrino + X-rays C) 6 protons = 2 heliums + 3 positrons + 3 neutrinos + gamma rays D) 4 protons = 1 helium 4 + a positron + a neutrino + gamma rays E) 4 protons = 1 helium 4 + 2 neutrinos + gamma rays 49) 50) The speed of light is 3.00 10 8 m/s. If 2.00 kg of mass is converted to energy, how much energy will be produced? A) 1.50 10 8 J B) 9.00 10 16 J C) 6.00 10 8 J D) 1.80 10 17 J E) 6.00 10 4 J 50) 8