CONCEPTUAL QUESTIONS ON 2ND LAW OF THERMODYNAMICS (10 points)1. Is a temperature difference necessary to operate a heat engine? State why orwhy not.2. Definitions of efficiency vary depending on how energy is being converted.Compare the definitions of efficiency for the human body and heat engines. Howdoes the definition of efficiency in each relate to the type of energy being convertedinto doing work?3. Why-other than the fact that the second law of thermodynamics says reversibleengines are the most efficient-should heat engines employing reversible processesbe more efficient than those employing irreversible processes? Consider thatdissipative mechanisms are one cause of irreversibility.PRACTICE PROBLEMS (20 points)1. (a) What is the efficiency of a cyclical heat engine in which 75.0 kJ of heattransfer occurs to the environment for every 95.0 kJ of heat transfer into theengine? (b) How much work does it produce for 100 kJ of heat transfer into theengine?2. The engine of a large ship does 2.00x10J of work with an efficiency of 5.00%.(a) How much heat transfer occurs to the environment? (b) How many barrels offuel are consumed, if each barrel produces 6.00x10°) of heat transfer whenburned?3. (a) How much heat transfer occurs to the environment by an electrical powerstation that uses 1.25x10") of heat transfer into the engine with an efficiency of42.0%? (b) What is the ratio of heat transfer to the environment to work output?(c) How much work is done?

Temperature difference is very necessary to drive a heat engine as the the work is extracted from…

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1. Is a temperature difference necessary to operate a heat engine? State why or why not.