Heat Engines, Energy, & Work

A heat engine absorbs 90 J of heat from its surroundings and uses 48 J to do work. How much energy does the engine release back to it surroundings?

• 42 J

• 138 J

• 48 J

• 90 J

If a gasoline engine takes in 550 J of heat energy and does 330 J of work, what is the engine's efficiency?

• 0.60

• 0.55

• 0.19

• 0.40

 a measure of the useful energy taken out of a process relative to the total energy that is put into the process

(a)  

• efficiency
• power
• density
• relativity
• flush
• velocity

A heat engine cannot transfer all the energy it absorbs as heat into work.

• True

• False

State the 1st Law of Thermodynamics in your own words:

State the 2nd Law of Thermodynamics in your own words:

A steam engine absorbs 690 J and releases 372 J in each cycle. What is the engine's efficiency?

• 0.46

• 0.69

• 0.64

• 0.54

A steam engine absorbs 690 J and releases 372 J in each cycle. How much energy was converted to work by the engine?

• 318 J

• 690 J

• 228 J

• 370 J

A diesel engine does 85 J of work and releases 49 J of heat in each cycle. What is the engine's efficiency?

• 0.634

• 0.850

• 0.494

• 0.543

A diesel engine does 88 J of work and releases 28 J of heat in each cycle. How much energy does it absorb in each cycle?

• 116 J

• 60 J

• 126 J

• 40 J