An Engine Manufacturer Makes the Claim That the Engine They

question 44

Multiple Choice

An engine manufacturer makes the claim that the engine they have developed will,on each cycle,take 100 J of heat out of boiling water at 100°C,do mechanical work of 80 J,and exhaust 20 J of heat at 10°C.What,if anything,is wrong with this claim?

• A) The heat exhausted must always be greater than the work done according to the second law of thermodynamics.
• B) This engine violates the first law of thermodynamics because 100 J + 20 J ≠ 80 J.
• C) An engine would operate by taking in heat at the lower temperature and exhausting heat at the higher temperature.
• D) The efficiency of this engine is greater than the ideal Carnot cycle efficiency.
• E) There is nothing wrong with this claim because 100 J = 20 J + 80 J.