Cyclic Processes: Heat Engines and Refrigerators

Outside a refrigerator?
1. Q_C
2. Q_H
Inside a refrigerator?
1. Q_C
2. Q_H
In the boiler of a heat engine?
1. Q_C
2. Q_H
In the radiator of a heat engine.
1. Q_C
2. Q_H
In the compressor of a refrigerator, the work done by the gas is:
1. +W
2. −W
Is this a heat engine or refrigerator?
1. Heat Engine
2. Refrigerator
Is this a heat engine or refrigerator?
1. Heat Engine
2. Refrigerator
Is this a heat engine or refrigerator?
1. Heat Engine
2. Refrigerator
Is this a heat engine or refrigerator?
1. Heat Engine
2. Refrigerator
150 J of heat is expelled from the back of a refrigerator to the surrounding room and 50 J of work is done in the compressor. How much heat is removed from the inside of the refrigerator?
1. 0 J
2. 50 J
3. 100 J
4. 200 J
20 J of heat is removed from the inside of a refrigerator and 50 J of work is done to compress the refrigerant. How much heat is released to the outside of the refrigerator?
1. 0 J
2. 20 J
3. 30 J
4. 50 J
5. 70 J
300 J of heat is added at the boiler of a heat engine. 100 J is removed by the radiator after the piston recompresses. How much work is done in the piston?
1. 0 J
2. 100 J
3. 200 J
4. 300 J
5. 400 J
50 J of work is done in the piston of a heat engine and 30 J is removed by the radiator as it cools the fluid. How much heat was added at the boiler?
1. 0 J
2. 20 J
3. 30 J
4. 50 J
5. 80 J
In a heat engine, which process occurs in the coils of the radiator as it loses heat to the outside environment?
1. Adiabatic
2. Isovolumetric
3. Isothermal
In a heat engine, which process occurs at the boiler as heat is gained from the burning of fuel?
1. Adiabatic
2. Isovolumetric
3. Isothermal
In a heat engine, which process occurs in the piston as it expands?
1. Adiabatic
2. Isovolumetric
3. Isothermal
In a refrigerator, which process occurs in the coils inside the refrigerator?
1. Adiabatic
2. Isovolumetric
3. Isothermal
In a refrigerator, which process occurs in the compressor?
1. Adiabatic
2. Isovolumetric
3. Isothermal
In a refrigerator, which process occurs in the expansion valve?
1. Adiabatic
2. Isovolumetric
3. Isothermal
In a refrigerator, which process occurs in the coils outside the refrigerator?
1. Adiabatic
2. Isovolumetric
3. Isothermal
In a closed heat engine 100 J of heat is gained in the boiler, 70 J of work is done by the engine, and 30 J of heat is lost in the radiator. What is the total change of internal energy during one complete cycle?
1. 0 J
2. 30 J
3. 70 J
4. 100 J
5. 200 J
Where is heat lost in a heat engine? (Where is Q negative?)
1. In the boiler
2. In the piston
3. In the radiator
Where is heat gained in a heat engine? (Where is Q negative?)
1. In the boiler
2. In the piston
3. In the radiator
Where is heat lost in a refrigerator? (Where is Q negative?)
1. Inside the refrigerator
2. In the compressor
3. Outside the refrigerator
4. In the expansion valve
Where is +W done by the gas in a refrigerator?
1. Inside the refrigerator
2. In the compressor
3. Outside the refrigerator
4. In the expansion valve
Where is heat gained in a refrigerator? (Where is Q positive?)
1. Inside the refrigerator
2. In the compressor
3. Outside the refrigerator
4. In the expansion valve
Where is -W done by the gas in a refrigerator?
1. Inside the refrigerator
2. In the compressor
3. Outside the refrigerator
4. In the expansion valve
A heat engine is 80% efficient. What percent of energy is input at the boiler as heat?
1. 0%
2. 20%
3. 80%
4. 100%
5. 120%
A 25% efficient heat engine does 100 J of work in the piston. How much heat is expelled as exhaust in the radiator?
1. 0 J
2. 25 J
3. 100 J
4. 200 J
5. 300 J
6. 400 J
A heat engine does 40 J of work and dumps 10 J of heat to a cold reservoir. How efficient is the engine?
1. 0%
2. 10%
3. 25%
4. 40%
5. 80%
6. 100%