Reading assignment: 22.2-22.4
Why would you want to use a heat pump (instead of an electric heater) to heat your house when 100% of
the energy in an electric heater can be converted directly to heat?
Isn't that more efficient? Explain.
In the third paragraph of Section 22.3 (8th edition), there's a caveat
that to be reversible, the gas must be able to return to its original state
*without changing the surroundings*. Give an example of a process that would be
considered reversible if not for that qualifier.
The Carnot engine is completely impractical---because it has to
operate reversibly, it would take it an infinite time to
complete a cycle. (Even operating *almost* reversibly, it will take a
long time to complete a cycle---it would still be impractical.) Why then do we bother? What is
important about this engine?
Why doesn't the Carnot engine have perfect efficiency?