What is true of the maximum possible efficiency of a heat engine?

Question

A. It is 100%.
B. It depends on the difference between the exhaust and intake temperatures.
C. It depends on the ratio between the exhaust and intake temperatures.
D. It depends on the intake temperature.

Answer 1

A heat engine can never be 100% efficent. The equation for efficiency is 1-Tl/Th

Or Th-Tl/Th

Tl= Temp low
Th=Temp high

Hope this gives you enough information to make the right decision.

Answer 2

It's not A, as that would violate the 2nd law of thermodynamics. Assuming it's a simple engine, it's probably C, but don't quote me on that. My undergrad thermo is a bit rusty.

Answer 3

C

Doug