Thermodynamics Quiz

A heat engine absorbs 290 J of heat from its surroundings and uses 191 J to do work. How much energy does the engine release back to it surroundings?

• 99 J

• 138 J

• 481 J

• 190 J

If a gasoline engine takes in 500 J of heat energy and does 360 J of work, what is the engine's efficiency?

• 0.60

• 0.54

• 0.72

• 0.40

A steam engine absorbs 390 J and releases 190 J in each cycle. What is the engine's efficiency?

• 0.51

• 0.39

• 0.49

• 0.54

A diesel engine absorbs 81 J of heat and releases 54 J of heat in each cycle. What is the engine's efficiency?

• 0.33

• 0.67

• 0.49

• 0.15

A gas engine takes in 75 kJ of heat energy per cycle and converts 43 kJ into work. How much heat does the engine release during each cycle?

• 32,000 J

• 77 kJ

• 54,000 J

• 23.8 kJ

In each cycle, a turbo engine absorbs 98 kJ of heat energy and releases 24 kJ of heat energy. How much work does the engine do each cycle?

• 74 kJ

• 87,500 J

• 122 kJ

• 21,000 J

Heat energy flows...

• To colder objects

• To hotter objects

• Back and forth

• In a circular manner

Which type of heat transfer requires direct contact with the heat source?

• Radiation

• Conduction

• Convection

Which type of heat transfer travels away from the heat source in all directions?

• Radiation

• Conduction

• Convection

Which type of heat transfer travels away from the heat source in a circular (rising and falling) motion?

• Radiation

• Conduction

• Convection