The Galactic Year is the time for our solar system to orbit the Galaxy; it is about:
A) 15 million years.
B) 225 million years.
C) 4.5 billion years.
D) 9.6 billion years.
E) 13.5 billion years.
B
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A rocket is launched from the origin with an acceleration of 20.0 
at an angle of 30.0 degrees above the horizontal. The launch acceleration lasts for 2.00 seconds at which time the fuel is exhausted. The rocket then falls with an acceleration of 9.80 
downward. What is the time it takes to reach maximum height?
A. 3.22 s B. 3.87 s C. 6.08 s D. 4.75 s E. 5.12 s
Aline says that the magnetic moment of an atom originates in the orbital angular momentum of the electron. Bevis says that it comes from the electron spin. Which one, if either, is correct, and why?
a. Aline, because only atoms, not electrons, can have angular momentum. b. Bevis, because only atoms, not electrons, can have angular momentum. c. Neither, because electron spin and orbital angular momentum always cancel exactly. d. Neither, because the magnetic moment of an atom comes only from the spin of the nucleus. e. Both, because both the orbital angular momentum and the spins of the electrons contribute to the magnetic moment of an atom.
A force of is exerted tangentially to a wheel of radius 0.340 m and causes an angular acceleration of 1.20 rad/s2. What is the moment of inertia of the wheel?
A) 4.78 kg ? m2 B) 3.59 kg ? m2 C) 5.98 kg ? m2 D) 7.17 kg ? m2
Our textbook discusses the cosmic calendar, a model of the history of the universe scaled to a single year. The length of time represented by one month on this cosmic calendar is therefore
A) about ten million years. B) about one million years. C) about one billion years. D) about ten billion years. E) about 1000 years.