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34 Cards in this Set
- Front
- Back
What is Newton's Law of Gravity? What does the "G" stand for?
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F=G*M1*M2/d^2
G is a constant number |
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How does the strength of gravitational attraction between two bodies depend on the distance between them?
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The distance between the two bodies is measured by the distance between the two centers; same force on both
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How does the gravitational force from the Earth acting on the moon compare with the gravitational force from the moon acting on the Earth?
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The farther you go out into space (away from Earth) the less gravitational force will be pulling you down
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T or F. A person's weight is just the gravitational force between the person and the Earth.
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True
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When a person is standing at the surface of the Earth, what should you use as the distance between the person and the Earth?
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Their head
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If a person is moved to a height of 1 Earth radius above the surface of the Earth, how does their weight compare to their weight at the surface of the Earth?
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2 Earth radius = 1/4
3 Earth radius = 1/9 |
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T or F. Newton was able to use his law of gravity, his 3 laws of motion (not kepler's 3 laws) and his newly invented calculus to explain kepler's 3 laws of planetary motion.
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True
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T or F. Newton showed that parabolas and hyperbolas are possible paths for objects moving past the sun.
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True
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What is the nature of electromagnetic radiation? Does it have mass and/or energy?
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They are in the photons (wave pocket). Do not have mass, but they do carry energy.
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At what velocity does all types of electromagnetic radiation travel?
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Speed of light
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What are the types of radiation that make up the electromagnetic spectrum? (in order from low to high frequency)
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Radio, microwaves, infrared, visible, ultraviolet, X-rays, gamma rays
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What is frequency?
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(f) the number of cycles of the wave that go past a point each second
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What is the relationship between wavelength, frequency and the speed of a wave?
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frequency= wavespeed/wavelength
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What is a photon?
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a wave packet
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What property of a wave does the energy of a photon depend on?
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frequency
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T or F. All objects with temperatures above absolute zero emit radiation.
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True
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T or F. Kirchoff's first law says that a hot solid or a hot high density gas will produce a continuous spectrum.
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True
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What is a continuous spectrum?
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a smooth distribution of light at all wavelengths
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T or F. The distribution of light with wavelength is given by curves called Planck curves or blackbody curves.
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True
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What produces an emission line spectrum? What does this type of spectrum look like?
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A hot/low density gas; (picture looks like four points sticking up)
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What produces an absorption line spectrum? What does this type of spectrum look like?
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by sending a continuous spectrum through a cool/low density gas; (picture looks like a curve with four points sticking down)
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What is the theory called for the formation of the solar system? And why?
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Nebular theory; because we believe that the sun and planets formed from a large interstellar cloud of gas.
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What do we believe caused the cloud to start to collapse and how do we think that we know this?
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We believe that a supernova compressed the cloud which formed the sun; radioactive elements came from this supernova explosion
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What is the protosun?
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a hot ball of contracting gas
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What are the volatile materials? What temp. do they condense into solid form? Where would it have been solid in the disk of gas around the protosun?
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Form ice when cold; < 150 K; on the ends of the disk
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What are the refractory materials? What temp. do they condense into solid form? Where would it have been solid in the disk of gas around the protosun?
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Rocks and metals; 500-1600 K; in the middle and far ends of the disk
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What is the "rock line"?
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the two inside lines on the disk of gas
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What is the "snow line"?
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the outer lines on disk of gas
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T or F. Planets will only begin to form out of solid particles in their vicinity.
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True
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Why do we think that microscopic solid particles in the disk of gas started growing larger in size?
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they turn into pebbles then bump into each other until they are boulders, then planetesimals
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What is a planetesimal?
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like asteroids; they are miles in diameter
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As planetesimals grew larger in size they would occasionally collide with enough energy to shatter apart; when the planetesimals were miles in diameter...
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Gravity assisted the bodies in staying together.
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The large Jovian planets must have started off as a "seed" of a planet. What (refractory and/or volatile) materials would this "seed" have formed?
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When they were about 10 times the mass of the Earth, gravity could start pulling in gas; it ended up being a continuous cycle of more gas=more gravity=more gas (a snowball effect)
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T or F. At some point these planets began holding on to the hydrogen and helium gas in their vicinity, at which time they grew into the giant gas planets that we see today.
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True
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