What do we mean when we say that the rotation curve for a spiral galaxy is "flat"?
A) Gas clouds orbiting far from the galactic center have approximately the same orbital speed as gas clouds located further inward.
B) The amount of light emitted by stars at different distances is about the same throughout the galaxy.
C) All the galaxy's mass is concentrated in its flat, gaseous disk.
D) The disk of a spiral galaxy is quite flat rather than spherical like the halo.
A
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If the same quantity of heat is added to both a 1-liter and a 2-liter container of water, the temperature change in the 1-liter container will be
A) less. B) the same. C) greater.
A person throws a ball horizontally from the top of a building that is 24.0 m above the ground level
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a. 13 m/s b. 4.2 m/s c. 26 m/s d. 2.7 m/s
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a. 12 rad c. 37 rad b. 25 rad d. 0.50 rad