Question 5

As a gasoline engine is running, an amount of gasoline containing 16,500 J of chemical potential energy is burned in 1 s. During that second, the engine does 3,300 J of work.

(a)

What is the engine's efficiency (in percent)?

%

(b)

The burning gasoline has a temperature of about 4,700F (2,900 K). The waste heat from the engine flows into air at about 84F (302 K). What is the Carnot efficiency (in percent) of a heat engine operating between these two temperatures?

%