Question 1

Which of the following is a TRUE statement?

Accepted Answer

A) The second law of thermodynamics is a consequence of the first law of thermodynamics. 
B) It is possible for heat to flow spontaneously from a hot body to a cold one or from a cold one to a hot one,depending on whether or not the process is reversible or irreversible. 
C) It is not possible to convert work entirely into heat. 
D) It is impossible to transfer heat from a cooler to a hotter body. 
E) All of these statements are false. 
A) The second law of thermodynamics is a consequence of the first law of thermodynamics. 
B) It is possible for heat to flow spontaneously from a hot body to a cold one or from a cold one to a hot one,depending on whether or not the process is reversible or irreversible. 
C) It is not possible to convert work entirely into heat. 
D) It is impossible to transfer heat from a cooler to a hotter body. 
E) All of these statements are false.

Question 2

As you increase the difference between the temperatures of the hot and cold reservoirs,a Carnot engine converts a larger and larger percent of the heat put into it into work.

Accepted Answer

A) True 
 B)False

Question 3

A Carnot engine operating between a warmer unknown temperature and a reservoir of boiling helium at 1.76 K has an efficiency of 11.0%.What is the warmer temperature?

Accepted Answer

A) 1.98 K 
B) 0.180 K 
C) 157 K 
D) 0.160 K 
A) 1.98 K 
B) 0.180 K 
C) 157 K 
D) 0.160 K

Question 4

A person reading a European newspaper finds that the low temperature the night before in Stockholm was -16°C.What is the equivalent temperature in degrees Fahrenheit?

Accepted Answer

A) 3.20000076°F 
B) -28.799999°F 
C) 23.1°F 
D) 8.9°F 
A) 3.20000076°F 
B) -28.799999°F 
C) 23.1°F 
D) 8.9°F

Question 5

A Carnot engine operates between two reservoirs with unknown temperatures.If the Carnot engine operates at 43% efficiency,what is the ratio of the kelvin temperatures of the reservoirs,Tc/Th?

Accepted Answer

A) 0.57 
B) 0.0021 
C) 0.0016 
D) 0.42999999 
A) 0.57 
B) 0.0021 
C) 0.0016 
D) 0.42999999

Question 6

Just as a heat engine is more and more effective as its efficiency approaches 1,a refrigerator is more and more effective as its coefficient of performance approaches 1.

Accepted Answer

A) True 
 B)False

Question 7

A system has a heat source supplying heat at a rate of 187 W and is doing work at a rate of 130.899998 W.At what rate is the internal energy of the system changing?

Accepted Answer

A) 56.1000022 W 
B) 317.900009 W 
C) -56.100002 W 
D) 187 W 
A) 56.1000022 W 
B) 317.900009 W 
C) -56.100002 W 
D) 187 W

Question 8

A fluid in an insulated,flexible bottle is heated by a high resistance wire and expands.If 9 kJ of heat is applied to the system and it does 5 kJ of work,how much does the internal energy change?

Accepted Answer

A) 4 kJ 
B) 14 kJ 
C) -4 kJ 
D) 45 kJ 
A) 4 kJ 
B) 14 kJ 
C) -4 kJ 
D) 45 kJ

Question 9

A heat pump with a COP of 4.90000007 absorbs heat from the atmosphere at a rate of 30 kW.At what rate is it doing work?

Accepted Answer

A) 6 kW 
B) 147 kW 
C) 117 kW 
D) 36 kW 
A) 6 kW 
B) 147 kW 
C) 117 kW 
D) 36 kW

Question 10

All real heat engines are less efficient than the Carnot engine.

Accepted Answer

A) True 
 B)False

Question 11

A refrigerator with a COP of 3.7 cools to 9.0°C.What is the high temperature,Th,needed to operate the refrigerator at 9.0°C?

Accepted Answer

A) 85°C 
B) 1052°C 
C) 11°C 
D) 42°C 
A) 85°C 
B) 1052°C 
C) 11°C 
D) 42°C

Question 12

What is the maximum efficiency of an engine operating between a reservoir in which ice and water coexist,and a reservoir in which water and steam coexist? The pressure is constant at 1.0 atmosphere for both.

Accepted Answer

A) 27% 
B) 0.27% 
C) 100% 
D) 1.0% 
A) 27% 
B) 0.27% 
C) 100% 
D) 1.0%

Question 13

An important feature of the Carnot cycle is that

Accepted Answer

A) its efficiency can be 100%. 
B) its efficiency depends only on the absolute temperature of the hot reservoir used. 
C) its efficiency is determined by the temperatures of the hot and cold reservoirs between which it works and by the properties of the working substance used,and on nothing else. 
D) it is an example of an irreversible process that can be analyzed exactly without approximations. 
E) no engine can be more efficient than a Carnot engine operating between the same two temperatures. 
A) its efficiency can be 100%. 
B) its efficiency depends only on the absolute temperature of the hot reservoir used. 
C) its efficiency is determined by the temperatures of the hot and cold reservoirs between which it works and by the properties of the working substance used,and on nothing else. 
D) it is an example of an irreversible process that can be analyzed exactly without approximations. 
E) no engine can be more efficient than a Carnot engine operating between the same two temperatures.

Question 14

A nuclear power plant has an actual efficiency of 39%.If 0.24999999 MW of energy are released from fission,how much electric power does the power plant produce?

Accepted Answer

A) 0.097 MW 
B) 9.7 MW 
C) 35 MW 
D) 0.35 MW 
A) 0.097 MW 
B) 9.7 MW 
C) 35 MW 
D) 0.35 MW

Question 15

A heat engine has a maximum possible efficiency of 0.800.If it operates between a deep lake with a constant temperature of 287.0 K and a hot reservoir,what is the temperature of the hot reservoir?

Accepted Answer

A) 1440 K 
B) 359 K 
C) 517 K 
D) 646 K 
A) 1440 K 
B) 359 K 
C) 517 K 
D) 646 K

Question 16

A thermometer flashes the temperature in Celsius and Fahrenheit along with the time.If it flashes 25°F,what will the thermometer flash in Celsius?

Accepted Answer

A) -3.9°C 
B) -18.1°C 
C) 77°C 
D) 13.9°C 
A) -3.9°C 
B) -18.1°C 
C) 77°C 
D) 13.9°C

Exam 11: Using Energy

Which of the following is a TRUE statement?

As you increase the difference between the temperatures of the hot and cold reservoirs,a Carnot engine converts a larger and larger percent of the heat put into it into work.

A Carnot engine operating between a warmer unknown temperature and a reservoir of boiling helium at 1.76 K has an efficiency of 11.0%.What is the warmer temperature?

A person reading a European newspaper finds that the low temperature the night before in Stockholm was -16°C.What is the equivalent temperature in degrees Fahrenheit?

A Carnot engine operates between two reservoirs with unknown temperatures.If the Carnot engine operates at 43% efficiency,what is the ratio of the kelvin temperatures of the reservoirs,Tc/Th?

Just as a heat engine is more and more effective as its efficiency approaches 1,a refrigerator is more and more effective as its coefficient of performance approaches 1.

A system has a heat source supplying heat at a rate of 187 W and is doing work at a rate of 130.899998 W.At what rate is the internal energy of the system changing?

A fluid in an insulated,flexible bottle is heated by a high resistance wire and expands.If 9 kJ of heat is applied to the system and it does 5 kJ of work,how much does the internal energy change?

A heat pump with a COP of 4.90000007 absorbs heat from the atmosphere at a rate of 30 kW.At what rate is it doing work?

All real heat engines are less efficient than the Carnot engine.

A refrigerator with a COP of 3.7 cools to 9.0°C.What is the high temperature,Th,needed to operate the refrigerator at 9.0°C?

What is the maximum efficiency of an engine operating between a reservoir in which ice and water coexist,and a reservoir in which water and steam coexist? The pressure is constant at 1.0 atmosphere for both.

An important feature of the Carnot cycle is that

A nuclear power plant has an actual efficiency of 39%.If 0.24999999 MW of energy are released from fission,how much electric power does the power plant produce?

A heat engine has a maximum possible efficiency of 0.800.If it operates between a deep lake with a constant temperature of 287.0 K and a hot reservoir,what is the temperature of the hot reservoir?

A thermometer flashes the temperature in Celsius and Fahrenheit along with the time.If it flashes 25°F,what will the thermometer flash in Celsius?

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Momentum

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Thermal Properties of Matter

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Electric Potential

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Electromagnetic Induction and Electromagnetic Waves

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A Carnot engine operates between two reservoirs with unknown temperatures.If the Carnot engine operates at 43% efficiency,what is the ratio of the kelvin temperatures of the reservoirs,T_c/T_h?

A refrigerator with a COP of 3.7 cools to 9.0°C.What is the high temperature,T_h,needed to operate the refrigerator at 9.0°C?