Collisions between galaxies:
A) are much rarer than collisions between stars.
B) can turn elliptical galaxies into spirals.
C) cause large numbers of stars to collide and explode.
D) cause the gas and dust clouds to collide, leading to rapid star formation.
E) are the best explanation for gamma-ray burst events.
D
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Briefly describe the steps in the big bang that provided the protons, neutrons, and electrons necessary for nucleosynthesis – the building of complex atoms
What will be an ideal response?
The magnetism of the Earth acts approximately as if it originates from a huge bar magnet within the Earth. Which of the following statements are true?
A. the north magnetic pole of the Earth is located at the Earth's North Pole B. the south magnetic pole of the Earth is located at the Earth's South Pole C. the Earth's magnetic field is vertical at the equator D. the Earths north magnetic pole is magnetically a south pole E. None of these statements are true.
Suppose that at a certain time a quanton has the (unrealistic) wave function shown below. 
If we were to perform an experiment to locate the quanton, what is the probability that the result will be ? 1 nm? (Assume that ? (x) = 0 at all points outside the picture.)
A. 1/8 B. 3/8 C. 1/12 D. 1/4 E. 5/12
When a positive charge is released and moves along an electric field line, it moves to a position of
a. lower potential and lower potential energy. b. lower potential and higher potential energy. c. higher potential and lower potential energy. d. higher potential and higher potential energy. e. greater magnitude of the electric field.