College Physics 11th Edition Volume 1 By Raymond Chris – Test Bank

ANSWERS TO EVEN-NUMBERED CONCEPTUAL QUESTIONS
12.2 The true statement is given in (d). Choice (c) is not true because the
area is unsigned while the work can be either positive or negative.
Choices (a) and (b) are false because the path on a PV diagram can go
in either direction.
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12.4 Temperature = a measure of molecular motion. Heat = the process
through which energy is transferred between objects by means of
random collisions of molecules. Internal energy = energy associated
with random molecular motions plus chemical energy, strain potential
energy, and an object’s other energy not associated with center of
mass motion or location.
12.6 The true statement is given in (c). Choice (a) is false because
temperature can change due to work W. Choice (b) is false because
temperature decreases during an adiabatic expansion (as negative
work is done on the gas). Choice (d) is false because temperature
increases during an adiabatic compression (as positive work is done
on the gas). Choice (e) is false for the same reason that that choice (d)
is false.
12.8 Choice (d) is impossible because it would require an efficiency greater
than 1 in violation of energy conservation.
12.10 (a) Q = 0 and W < 0 so ΔU < 0 and U decreases.
(b) W = 0 and Q < 0 so ΔU < 0 and U decreases.
(c) W = 0 and Q = 0 so ΔU = 0 and U remains constant.
(d) The internal energy of an ideal gas is proportional to its
temperature so as temperature increases, internal energy
Topic 12
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a publicly accessible website, in whole or in part.
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increases.
12.12 (a) Entropy change is proportional to Q so the cooler object will have
an entropy increase as it absorbs energy and warms. The correct
answer is object B.
(b) Object A loses energy to B so its entropy decreases (QA < 0). The
correct answer is object A.
(c) QA = −QB and entropy change is inversely proportional to
temperature, so the cooler object will have the greater magnitude
of entropy change. TA > TB so the correct answer is object B.
12.14 Heat is not a form of energy. Rather, it is the process of transferring
energy through microscopic collisions between atoms or molecules.
An object having a large mass and/or a high specific heat may be at a
low temperature and still contain more internal energy than does a
higher temperature, low-mass object.
12.16 The Clausius statement of the second law of thermodynamics says
that in any thermodynamics process, reversible or irreversible, the
total entropy of the universe must either remain constant (reversible
process) or increase (irreversible process). Thus, if in a
thermodynamics process, the entropy of a system changes by −6 J/K,
the entropy of the environment (i.e., the rest of the universe) must