Ch 24 Thermodynamics
The lowest possible temperature in nature is
-273 degrees C.
80 joules of heat is added to a system that performs 55 Joules of work. The internal energy change of the system is
25 J
The ideal efficiency for a heat engine operating between temperatures of 2050 K and 310 K is
85%
Air high in the atmosphere that plunges downward tends to cool
False
It is possible to wholly convert a given amount of heat energy into mechanical energy
False
Efficiency in a heat engine is increased when there is a greater difference in input and output temperatures
True
It is possible to totally convert a given amount of mechanical energy into heat
True
Systems left alone tend to move to a state of greater entropy
True
Whenever heat is added to system, it transforms to an equal amount of some other form of energy
True
Adiabatic process occur in
all of the above
When mechanical work is done on a system, there can be an increase in its
both of the above
The first law of thermodynamics is a restatement of the
conservation of energy
In buildings that are electrically heated, turning the lights on
doesn't waste energy
Pull a closed plastic bag of dry air quickly down from a high elevation and the bag of air will become
hotter
When a volume of air compressed and no heat enters or leaves, the air temperature will
increase
As a system becomes more disordered, entropy
increases
Entropy measures
messiness
Ceramic automobile engines that operate at higher temperatures will be
more efficient
Systems that are left alone tend to move toward a state of
more entropy
Entropy is closely related to the
second law of thermodynamics
Two identical blocks of iron, one at 10 degrees C and the other at 20 degrees C, are put in contacts. Suppose the cooler block cools to 5 degrees C and the warmer block warms to 25 degrees C. This would violate the
second law of thermodynamics