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Why Is the Sun Very Dense on the Inside? Why Is the Sun Very Dense on the Inside? Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review Why does the Sun shine? Why does the Sun shine? Why is the Sun very dense on the inside? Why is the Sun very dense on the inside? a) It is on fire. a) It is on fire. a) Denser materials sank to its center. a) Denser materials sank to its center. b) chemical energy b) chemical energy b) Pressure of the overlying gas keeps the density b) Pressure of the overlying gas keeps the density c) gravitational energy c) gravitational energy high. high. d) nuclear fusion d) nuclear fusion c) It formed from dense material. c) It formed from dense material. e) nuclear fission e) nuclear fission d) Nuclear fusion increases the density in the core by d) Nuclear fusion increases the density in the core by changing hydrogen into helium. changing hydrogen into helium. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review What conditions are required for nuclear fusion What conditions are required for nuclear fusion What is a hydrogen nucleus–the particle that What is a hydrogen nucleus–the particle that of hydrogen to occur? of hydrogen to occur? fuses into helium in the Sun? fuses into helium in the Sun? a) a temperature of millions Kelvin a) a temperature of millions Kelvin a) a neutron a) a neutron b) high density b) high density b) a proton b) a proton c) the presence of uranium c) the presence of uranium c) an electron c) an electron d) all of the above d) all of the above d) a positron d) a positron e) A and B e) A and B © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review What kind of radiation do you think shines out What kind of radiation do you think shines out If the Sun's core went out of balance and If the Sun's core went out of balance and of the core of the Sun? of the core of the Sun? shrank a little, what would happen? shrank a little, what would happen? a) visible light a) visible light a) The density would decrease, and fusion would slow a) The density would decrease, and fusion would slow b) infrared light b) infrared light down, releasing less energy. down, releasing less energy. c) X-ray light c) X-ray light b) The density would increase, and fusion would b) The density would increase, and fusion would speed up, releasing more energy. speed up, releasing more energy. d) ultraviolet light d) ultraviolet light e) gamma rays e) gamma rays c) The whole Sun would shrink. c) The whole Sun would shrink. d) Not much would change. d) Not much would change. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review If the fusion in the Sun's core sped up slightly, If the fusion in the Sun's core sped up slightly, How do photons get from the core of the Sun to How do photons get from the core of the Sun to releasing more energy, what would happen? releasing more energy, what would happen? the surface? the surface? a) The entire Sun would become hotter. a) The entire Sun would become hotter. a) They bounce from atom to atom, being absorbed a) They bounce from atom to atom, being absorbed b) The core would expand. b) The core would expand. and reemitted as they make their way to the and reemitted as they make their way to the c) The color of the Sun would change. c) The color of the Sun would change. surface. surface. b) They are brought to the surface by conduction. b) They are brought to the surface by conduction. d) all of the above d) all of the above c) They are brought to the surface by convection. c) They are brought to the surface by convection. d) none of the above d) none of the above © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review By the time photons reach the surface of the By the time photons reach the surface of the If we can't see the Sun's interior, how do we If we can't see the Sun's interior, how do we Sun, they are mostly Sun, they are mostly know what it is like? know what it is like? a) infrared light. a) infrared light. a) observations of sunquakes a) observations of sunquakes b) visible light. b) visible light. b) observations of neutrinos b) observations of neutrinos c) ultraviolet light. c) ultraviolet light. c) our understanding of gravitational equilibrium c) our understanding of gravitational equilibrium d) X rays. d) X rays. d) all of the above d) all of the above e) gamma rays. e) gamma rays. e) B and C e) B and C © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review The Sun's visible surface, or photosphere, has The Sun's visible surface, or photosphere, has Since the Sun's outer atmosphere, or corona, is Since the Sun's outer atmosphere, or corona, is regions of strong magnetic field called regions of strong magnetic field called millions of degrees but not very dense, millions of degrees but not very dense, a) granulation. a) granulation. a) we can't really see it in any wavelength. a) we can't really see it in any wavelength. b) magnetic traps. b) magnetic traps. b) we see it very clearly in visible light. b) we see it very clearly in visible light. c) magnetic lines. c) magnetic lines. c) we see X rays coming from it. c) we see X rays coming from it. d) sunspots. d) sunspots. d) we only see the lower layers of the Sun's d) we only see the lower layers of the Sun's e) sundogs. e) sundogs. atmosphere, which are much more dense. atmosphere, which are much more dense. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review What is the solar activity cycle? What is the solar activity cycle? How does solar activity affect Earth? How does solar activity affect Earth? a) the balance of pressure and gravity in the Sun's a) the balance of pressure and gravity in the Sun's a) It can make beautiful aurora. a) It can make beautiful aurora. core core b) It can cause geomagnetic storms. b) It can cause geomagnetic storms. b) the process of fusing hydrogen into helium b) the process of fusing hydrogen into helium c) It can damage satellites. c) It can damage satellites. c) the 11-year cycle of changes in the occurrence of c) the 11-year cycle of changes in the occurrence d) It can disrupt electrical power. d) It can disrupt electrical power. sunspots, flares, and solar wind of sunspots, flares, and solar wind e) all of the above e) all of the above d) the process by which photons from the Sun's core d) the process by which photons from the Sun's core make their way to the surface make their way to the surface © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. © 2014 Pearson Education, Inc. Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review Chapter 14-16 Review If fusion in the solar core ceased today, If fusion in the solar core ceased today, Which of the following can be used to directly Which of the following can be used to directly worldwide panic would break out tomorrow worldwide panic would break out tomorrow measure the Sun's mass? measure the Sun's mass? as the Sun began to grow dimmer. as the Sun began to grow dimmer. a) solar luminosity and Earth-Sun distance a) solar luminosity and Earth-Sun distance a) Yes, because Earth would quickly freeze over. a) Yes, because Earth would quickly freeze over. b) solar temperature and Earth-Sun distance b) solar temperature and Earth-Sun distance b) Yes, because Earth would no longer be bound to the b) Yes, because Earth would no longer be bound to the solar system and would drift into space. solar system and would drift into space. c) solar rotation rate and Earth-Sun distance. c) solar rotation rate and Earth-Sun distance. c) Yes, because the Sun would collapse and the planets c) Yes, because the Sun would collapse and the planets d) Earth's mass and orbital period d) Earth's mass and orbital period would soon follow. would soon follow. e) The Venus-Sun distance and the length of a e) The Venus-Sun distance and the length of a d) No, it takes thousands of years for photons created in d) No, it takes thousands of years for photons created in Venusian year Venusian year nuclear reactions at the solar core to reach the surface.
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