Thermodynamics Efficiency

The maximum efficiency of a heat engine that operates between temperatures of 1500 K in the firing chamber and 600 K in the exhaust chamber is most nearly

• 33%

• 40%

• 60%

• 67%

• 100%

In each cycle of a certain Carnot engine, 100 joules of heat is absorbed from the high‑temperature reservoir and 60 joules is exhausted to the low‑temperature reser­voir. What is the efficiency of the engine?

• 40%

• 60%

• 67%

• 150%

• 167%

The theoretical (Carnot) efficiency of a heat engine operating between 600ºC and 100ºC is:

• 16.7%

• 20.0%

• 42.7%

• 57.3%

• 83.3%

A heat engine takes in 200 J of thermal energy and performs 50 J of work in each cycle. What is its efficiency?

• 50 %

• 40 %

• 25 %

• 20 %

• 12 %

An engine operates on the cycle shown in the PV diagram below. The working substance of the engine is an ideal monatomic gas. The processes A → B and C → D are isobaric, while processes B → C and D → A are isochoric.

What is the efficiency of a Carnot engine operating between the same maximum and minimum temperatures as this engine?

• 1/6

• 1/3

• 1/2

• 3/5

• 5/6

What would be the efficiency of the heat engine diagramed as shown below?

• 300 %

• 133 %

• 75 %

• 33 %

• 25 %