Astronomy Chapter 11 Answers – Flashcards
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The structure of the Sun is determined by both the balance between the forces due to __ and gravity and the balance between energy generation and energy__
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pressure; loss
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What are the steps in the fusion of hydrogen into helium?
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1. Two hydrogen nuclei collide and become 2^He; a positron is emitted, a neutrino is emitted 2. Two gamma rays are emitted 3. One deuterium nucleus and one hydrogen nucleus collide and become 3^He, one gamma ray is emitted 4. Two ^3He collide and become ^4He, Two hydrogen nuclei are emitted
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As energy moves from the Sun's core toward its surface, it first travels by __ , then by __, and then by ___
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radiation; convection; radiation
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The physical model of the Sun's interior has been confirmed by observations of
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neutrinos and seismic vibrations
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Sunspots, flares, prominences, and coronal mass ejections are all caused by:
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magnetic activity on the Sun
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Ultimately, the Sun's energy comes from
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the mass of hydrogen nuclei
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Radiation transports energy by moving __, while convection transports energy by moving ___
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light; matter
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The temperature and density change abruptly at the interface between
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the chromosphere and the corona
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The solar wind
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creates a teardrop-shaped bubble around the Solar System
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Sunspots peak every __ years, a consequence of the __ year magnetic solar cycle
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11; 22
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T or F: Hydrostatic equilibrium is the balance between energy production and loss
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False
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T or F: Six hydrogen nuclei are involved in the proton-proton chain, although only four of them wind up in the helium nucleus
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True
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T or F: Photons travel outward through the Sun because the innermost part of the Sun is more crowded with photons than the outer parts.
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True
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T or F: Neutrinos make it out of the Sun faster than photons. This means they travel faster than photons
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False
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T or F: Sunspots can be comparable in size to Earth
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True
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Hydrostatic equilibrium inside the Sun means that
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radiation pressure balances the weight of the outer layers pushing down
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The energy that is emitted from the Sun is produced
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in the core, by nuclear fusion
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In the proton-proton chain , 4 hydrogen nuclei are converted to a helium nucleus. This does not happen spontaneously on Earth because the process requires
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very high temperatures and pressures
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The solar neutrino problem pointed to a fundamental gap in our knowledge of
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neutrinos
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Sunspots appear dark because
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they are cooler than their surroundings
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Sunspots change in number and location during the solar cycle. This phenomenon is connected to
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the rotation rate of the Sun
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Suppose an abnormally large amount of hydrogen suddenly burned in the core of the Sun. Which of the following would be observed first?
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the Sun would emit more neutrinos
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The solar corona has a temperature of more than a million kelvins; the photosphere has a temperature of only about 6000 K. Why isn't the corona much brighter than the photosphere?
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the corona has much lower density
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The Sun rotates once every 25 days relative to the stars. The Sun rotates once every 27 days relative to Earth. Why are these two numbers different?
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Earth moves in its orbit during this time
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Some engineers and physicists have been working to solve the world energy supply problem by constructing power plants that would convert hydrogen to helium. Our Sun seems to have solved this problem. On Earth, what is the major obstacle to this solution?
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It is difficult to achieve the temperatures of the interior of the Sun/ creating a containment system, that would not be consumed by the necessary conditions of density and temperature, requires technology not yet developed
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The Sun's energy comes from:
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the mass of hydrogen nuclei
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The solar corona has a temperature of more than a million kelvins. The photosphere has a temperature of only about 6000 K. Why isn't the corona much much brighter than the photosphere?
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The corona has a much lower density
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The Sun rotates every 25 days relative to the stars. The Sun rotates once every 27 days relative to Earth. Why are these two numbers different?
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The Earth moves in its orbit during this time.
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Fusion of hydrogen into helium:
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1) Two hydrogen nuclei collide and form (2)H; A positron and a neutrino are emitted 2) Two gamma rays are emitted 3) One deuterium nucleus and one hydrogen nucleus collide and become (3)He; One gamma ray is emitted 4) Two (3)He and become (4)He; Two hydrogen nuclei are emitted
