As an object moves from point A to point B only two forces act on it: one force is nonconservative and does ?30 J of work, the other force is conservative and does +50 J of work. Between A and B,
a. the kinetic energy of object increases, mechanical energy decreases
b. the kinetic energy of object decreases, mechanical energy decreases.
c. the kinetic energy of object decreases, mechanical energy increases.
d. the kinetic energy of object increases, mechanical energy increases.
e. None of the above.
a
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Compared to its neutral atom, an ion has the same number of
A) protons and neutrons B) protons but a different number of neutrons C) protons but a different number of electrons D) neutrons but a different number of protons
A metal rod of length L in a region of space where a constant magnetic field points into the page rotates about an axis through its center at constant angular velocity ?. The ends, A and E, make contact with a split ring that connects to an external circuit. The current in the external circuit of resistance R has magnitude
a.
0.
b.
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