Relativity dealing with gravitation is known as:
a. inertial relativity.
b. gravitational relativity.
c. Galilean relativity.
d. general relativity.
[Ques. 2] If the nonzero momentum of a particle with mass is doubled, what happens to its total energy?
a. It also doubles.
b. It increases, more than doubling.
c. It stays the same since total energy is a constant for a given particle.
d. It increases, but less than doubling.
[Ques. 3] When one compares the relativistic kinetic energy to the classically calculated kinetic energy for a moving object, at which of the speeds listed below does the classical calculation give a greater value than the relativistic calculation?
a. 0.2c
b. 0.5c
c. 0.707c
d. None of the above values will give such a result.
[Ques. 4] Through what potential difference would an electron initially at rest need to be accelerated to have its total energy be five times its rest energy? (me = 9.11 1031 kg, c = 3.00 108 m/s, and qe = 1.6 1019 C)
a. 1.6E19 V
b. 2.6E+6 V
c. 2.0E+6 V
d. 210 V
e. 6.8E3 V
[Ques. 5] In an x-ray tube, high-speed electrons are slammed into a lead target, giving off x-rays. If the electrons are accelerated from rest through a potential difference of 160 000 volts, what speed do they have when they strike the target? (qe = 1.6 1019 C, me = 9.11 1031 kg, and c = 3.00 108 m/s)
a. 0.79c
b. 0.65c
c. 0.83c
d. 0.49c
e. 0.48c
[Ques. 6] A lump of uranium has a mass of 2.0 kg, and begins at rest. Half of the lump's mass is going to be totally converted into kinetic energy of the other half. After this is done, how fast is the remaining half going?
a. 0.60c
b. 0.80c
c. 0.87c
d. 1.0c
[Ques. 7] A satellite is powered by a small nuclear generator that puts out 10 W. How much matter is converted into energy over the 20-year life span of the generator?
a. 70 g
b. 70 g
c. 7 g
d. 7 kg
e. 4 mg
[Ques. 8] A spaceship of mass 106 kg is to be accelerated to 0.75c. How much energy does this require?
a. 13.61 1023 J
b. 5.95 1023 J
c. 5.06 1022 J
d. 4.61 1022 J
e. 27.00 1023 J
[Ques. 9] The mass of a proton at rest is m. If the proton is moving so fast that its total energy is three times its rest energy, then what is the kinetic energy of the proton?
a. mc2
b. 2mc2
c. 3mc2
d. 4mc2
[Ques. 10] Suppose an object whose mass is m is moving with a speed of 0.8c. Which is the correct expression for its kinetic energy?
a. K = mv2/2
b. K = mc2
c. K = ( 1)mc2
d. Answers a and c are both correct.
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