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15 Cards in this Set
- Front
- Back
What is the Big Bang?
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ANSWER: Theory that the universe was created by a massive explosion. Following the explosion, protons & neutrons began to form, as well as atoms of hydrogen & helium and the first known conversion of energy into matter was completed.
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What would have happened if the universe had expanded too rapidly?
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ANSWER: Only hydrogen would have formed.
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What would have happened if theuniverse had expanded at a slower rate?
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ANSWER: More complex elements would have had time to form, and the universe would today be made up of mostly heavy elements.
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Which elements were the first to form after the Big Bang and why?
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ANSWER: Hydrogen & helium formed because of the rate of expansion.
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What are galaxies doing in an expanding universe?
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ANSWER: Moving away from each other.
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What is the Doppler Effect?
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ANSWER: An apparent change in wavelength of any wave motion caused by the relative position of an observer versus the wave source.
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During the normal life of a star, where does the energy and heat come from?
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ANSWER: From the conversion of hydrogen into helium.
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When did iron begin to form in the universe?
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ANSWER: After the formation of the lighter elements
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When do some astronomers believe that the Big Bang occurred?
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ANSWER: 20 billion years ago
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What color is the spectrum of a galaxy that is moving away from the Earth?
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ANSWER: Red--longer wavelengths of the spectrum
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What two factors determine whether a planet retains an atmosphere?
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ANSWER: A planet's ability to retain an atmosphere depends on its mass and temperature.
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How does chemical differentiation work?
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ANSWER: Heavier elements move toward the core, and the lighter elements move toward the surface.
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What is the protosun?
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ANSWER: The material that eventually became the sun.
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How do terrestrial and Jovian planets differ from each other?
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ANSWER: Jovian planets have very think gaseous atmospheres, while the terrestrial planets have very thin atmospheres.
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What are Jovian planets mainly composed of?
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ANSWER: Water, carbon dioxide, ammonia, and methane.
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