Ranking Work Output of Heat Engines

1. Chapter 12

2. Rank in order, from largest to smallest, the work Wout performed by these four heat engines. • Wb > Wa > Wc > Wd • Wb > Wa > Wb > Wc • Wb > Wa > Wb = Wc • Wd > Wa = Wb > Wc • Wd > Wa > Wb > Wc

3. Rank in order, from largest to smallest, the work Wout performed by these four heat engines. • Wb > Wa > Wc > Wd • Wb > Wa > Wb > Wc • Wb > Wa > Wb = Wc • Wd > Wa = Wb > Wc • Wd > Wa > Wb > Wc

4. It’s a really hot day and your air conditioner is broken. Your roommate says, “Let’s open the refrigerator door and cool this place off.” Will this work? • Yes. • It might, but it will depend on how hot the room is. • No.

5. It’s a really hot day and your air conditioner is broken. Your roommate says, “Let’s open the refrigerator door and cool this place off.” Will this work? • Yes. • It might, but it will depend on how hot the room is. • No.

6. What is the thermal efficiency of this heat engine? • 0.10 • 0.25 • 0.50 • 4 • Can’t tell without knowing QC.

7. What is the thermal efficiency of this heat engine? • 0.10 • 0.25 • 0.50 • 4 • Can’t tell without knowing QC.

8. What, if anything, is wrong with this refrigerator? • It violates the first law of thermodynamics. • It violates the second law of thermodynamics. • It violates the third law of thermodynamics. • Nothing is wrong.

9. What, if anything, is wrong with this refrigerator? • It violates the first law of thermodynamics. • It violates the second law of thermodynamics. • It violates the third law of thermodynamics. • Nothing is wrong.

10. Could this heat engine be built? • Yes. • No. • It’s impossible to tell without knowing what kind of cycle it uses.

11. Could this heat engine be built? • Yes. • No. • It’s impossible to tell without knowing what kind of cycle it uses.

12. What is the generic name for a cyclical device that transforms heat energy into work. • Refrigerators • Thermal Motors • Heat Engines • Carnot Cycles • Otto processors

13. What is the generic name for a cyclical device that transforms heat energy into work. • Refrigerators • Thermal Motors • Heat Engines • Carnot Cycles • Otto processors

14. The area enclosed within a pV curve is • the work done by the system during one complete cycle. • the work done on the system during one complete cycle. • the thermal energy change of the system during one complete cycle. • the heat transferred out of the system during one complete cycle.

15. The area enclosed within a pV curve is • the work done by the system during one complete cycle. • the work done on the system during one complete cycle. • the thermal energy change of the system during one complete cycle. • the heat transferred out of the system during one complete cycle.

16. The maximum possible efficiency of a heat engine is determined by • its design. • the amount of heat that flows. • the maximum and minimum pressure. • the compression ratio. • the maximum and minimum temperature.

17. The maximum possible efficiency of a heat engine is determined by • its design. • the amount of heat that flows. • the maximum and minimum pressure. • the compression ratio. • the maximum and minimum temperature.

18. The engine with the largest possible efficiency uses a • Brayton cycle. • Joule cycle. • Carnot cycle. • Otto cycle. • Diesel cycle.

19. The engine with the largest possible efficiency uses a • Brayton cycle. • Joule cycle. • Carnot cycle. • Otto cycle. • Diesel cycle.