In a heat pump,
a. heat is used to do work.
b. heat flows spontaneously.
c. the same process is used as in a heat engine.
d. work is used to transfer heat.
[Ques. 2] How many grams of U-235 must be fissioned every day to produce 1000 MW of electricity in a nuclear power plant that is 1/3 efficient? Assume 208 MeV/fission and 1 MeV = 1.6 1013 J
[Ques. 3] The longest-daylight day for people in the Southern Hemisphere at latitudes greater than 30S occurs at the
a. summer solstice.
b. vernal equinox.
c. winter solstice.
d. autumnal equinox.
[Ques. 4] If 700 Joules of heat is added to a system, while the system does 550 Joules, by how much does the internal energy increase?
a. 1250 J
b. 150 J
c. 700 J
d. 150 J
e. 1250 J
[Ques. 5] The theory of nuclear astrophysics is that all the heavy elements like uranium are formed in the interior of massive stars. These stars eventually explode, releasing these elements into space. If we assume that at the time of the explosion there were equal amount of U-235 and U-238, how long ago did the star(s) explode that released the elements that formed our Earth? The present U-235/U-238 ratio is 0.0070 . The half-lives of U-235 and U-238 are 0.7 109 yr and 4.47 109 yr.
[Ques. 6] The number of daylight hours at 35N is greatest during the month of
a. May.
b. August.
c. June.
d. July.
[Ques. 7] If 700 Joules of heat is added to a system, and the internal energy increases by 450 Joules, how much work is done by the system?
a. 1150 J
b. 250 J
c. 700 J
d. 250 J
e. 1150 J
[Ques. 8] A beam of high-energy -particles is incident upon a person and deposits 0.35 J of energy in 0.80 kg of tissue. What dose in rads and what equivalent dose in rems does the individual receive? RBE = 20
[Ques. 9] The number of daylight hours before 12 noon is ______________ the number of daylight hours past 12 noon.
a. greater than
b. less than
c. approximately the same as
[Ques. 10] The impossibility of reaching a temperature of absolute zero is incorporated in
a. the third law of thermodynamics.
b. the first law of thermodynamics.
c. the second law of thermodynamics.
d. an increase in entropy.
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