Multiple choice question for engineering

Set 1

1. 20 J of heat is supplied to the system and work done on the system is 15 J. What is the change in internal energy of the system?
a) 15 J
b) 20 J
c) 25 J
d) 35 J

Answer

Answer: d [Reason:] For the given process ∆U = – (-W) +Q.

2. 25 J of heat is supplied to a system and work done by the system is 15 J. What is the change in internal energy of the system?
a) 10 J
b) 20 J
c) 25 J
d) 35 J

Answer

Answer: a [Reason:] For the given process ∆U = -W +Q.

3. If work done on a system is 20 J and a heat of 15 J is taken out, what is the change in internal energy of the system?
a) 5 J
b) 10 J
c) 20 J
d) 30 J

Answer

Answer: a [Reason:] For the given process ∆U = W – Q.

4. 25 J of heat is supplied to a system and work done by the system is 10 J. What is the change in internal energy of the system?
a) 10 J
b) 15 J
c) 25 J
d) 35 J

Answer

Answer: b [Reason:] For the given process ∆U = -W +Q.

5. 20 J of heat is supplied to a system and change in internal energy of the system is 10 J. If 2 J of heat is taken out then how much was work done on the system?
a) -2 J
b) -4 J
c) -6 J
d) -8 J

Answer

Answer: d [Reason:] For the given process ∆U = W +Q.

6. A system does a work of 15 J and the change in internal energy of the system is 10 J, what is the heat supplied to the system?
a) – 15 J
b) 15 J
c) – 25 J
d) 25 J

Answer

Answer: d [Reason:] 10 = – 15 + Q.

7. 1 Kg of steam that contains an internal energy of 10 J/Kg, if 10 J of heat is supplied to the system, what is the resultant internal energy of the system?
a) 10 J/ Kg
b) 20 J/Kg
c) 30 J/Kg
d) 40 J/Kg

Answer

Answer: b [Reason:] 10 = 1(U – 10).

8. 2 Kg of steam that contains an internal energy of 20 J/Kg, if 50 J of heat is supplied to the system, what is the resultant internal energy of the system?
a) 45 J/Kg
b) 40 J/Kg
c) 35 J/Kg
d) 20 J/Kg

Answer

Answer: a [Reason:] 50 = 2(U – 20).

9. Specific internal energy is internal energy per unit ________ of the system.
a) Mass
b) Mole
c) Volume
d) None of the mentioned

Answer

Answer: a [Reason:] Specific internal energy is internal energy per unit mass of the system.

10. For an isolated system, internal energy
a) Can change
b) Can`t Change
c) May change
d) None of the mentioned

Answer

Answer: b [Reason:] The walls does not allow to pass neither mass nor energy.

Set 2

1. 20 J of heat is supplied to the system and work done on the system is 15 J. What is the change in internal energy of the system?
a) 15 J
b) 20 J
c) 25 J
d) 35 J

Answer

Answer: d [Reason:] For the given process ∆U = – (-W) +Q.

2. 25 J of heat is supplied to a system and work done by the system is 15 J. What is the change in internal energy of the system?
a) 10 J
b) 20 J
c) 25 J
d) 35 J

Answer

Answer: a [Reason:] For the given process ∆U = -W +Q.

3. If work done on a system is 20 J and a heat of 15 J is taken out, what is the change in internal energy of the system?
a) 5 J
b) 10 J
c) 20 J
d) 30 J

Answer

Answer: a [Reason:] For the given process ∆U = W – Q.

4. 25 J of heat is supplied to a system and work done by the system is 10 J. What is the change in internal energy of the system?
a) 10 J
b) 15 J
c) 25 J
d) 35 J

Answer

Answer: b [Reason:] For the given process ∆U = -W +Q.

5. 20 J of heat is supplied to a system and change in internal energy of the system is 10 J. If 2 J of heat is taken out then how much was work done on the system?
a) -2 J
b) -4 J
c) -6 J
d) -8 J

Answer

Answer: d [Reason:] For the given process ∆U = W +Q.

6. A system does a work of 15 J and the change in internal energy of the system is 10 J, what is the heat supplied to the system?
a) – 15 J
b) 15 J
c) – 25 J
d) 25 J

Answer

Answer: d [Reason:] 10 = – 15 + Q.

7. 1 Kg of steam that contains an internal energy of 10 J/Kg, if 10 J of heat is supplied to the system, what is the resultant internal energy of the system?
a) 10 J/ Kg
b) 20 J/Kg
c) 30 J/Kg
d) 40 J/Kg

Answer

Answer: b [Reason:] 10 = 1(U – 10).

8. 2 Kg of steam that contains an internal energy of 20 J/Kg, if 50 J of heat is supplied to the system, what is the resultant internal energy of the system?
a) 45 J/Kg
b) 40 J/Kg
c) 35 J/Kg
d) 20 J/Kg

Answer

Answer: a [Reason:] 50 = 2(U – 20).

9. Specific internal energy is internal energy per unit ________ of the system.
a) Mass
b) Mole
c) Volume
d) None of the mentioned

Answer

Answer: a [Reason:] Specific internal energy is internal energy per unit mass of the system.

10. For an isolated system, internal energy
a) Can change
b) Can`t Change
c) May change
d) None of the mentioned

Answer

Answer: b [Reason:] The walls does not allow to pass neither mass nor energy.

Set 3

1. Change in the internal energy for a steady-state system is always ___________
a) Positive
b) Negative
c) Zero
d) None of the mentioned

Answer

Answer: c [Reason:] Change in the internal energy for a steady-state system is always zero.

2. For a steady state system, 10 J of heat is supplied to the system, what is the work done by the system?
a) 10 J
b) 20 J
c) 30 J
d) 40 J

Answer

Answer: a [Reason:] Change in the internal energy for a steady-state system is always zero so Q = W.

3. If x J of work is done on a steady system, what is the heat for the system?
a) + x J
b) –x J
c) 0 J
d) None of the mentioned

Answer

Answer: b [Reason:] Change in the internal energy for a steady-state system is always zero so Q + W= 0.

4. 10 J of heat is removed from a steady state system, what is the work done on the system?
a) – 10 J
b) 10 J
c) – 5 J
d) 5 J

Answer

Answer: b [Reason:] 0 = – 10 + W.

5. 25 J of work is done by a steady state system, what is the heat supplied to the system?
a) – 25 J
b) 25 J
c) 20 J
d) – 20 J

Answer

Answer: b [Reason:] 0 = – 15 + Q.

6. 20 J of heat is supplied to a system and a work of 30 J performed on it. If 50 J of heat is removed from the system, which type of system is it?
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: a [Reason:] ∆E = 0.

7. 10 J of heat is supplied to a system and a work of 30 J performed on it. If 50 J of heat is removed from the system, which type of system is it?
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: b [Reason:] ∆E is not equal to zero.

8. If 25 J is work is done on a system and same amount of heat is also supplied. What kind of system is it?
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: b [Reason:] ∆E is not equal to zero.

9. If 25 J is work is done by a system and same amount of heat is also supplied to the system. What kind of system is it?
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: a [Reason:] ∆E is equal to zero.

10. There must be no accumulation of mass or energy over the time period of interest in a _________
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: a [Reason:] There must be no accumulation of mass or energy over the time period of interest in a Steady state.

Set 4

1. Change in the internal energy for a steady-state system is always ___________
a) Positive
b) Negative
c) Zero
d) None of the mentioned

Answer

Answer: c [Reason:] Change in the internal energy for a steady-state system is always zero.

2. For a steady state system, 10 J of heat is supplied to the system, what is the work done by the system?
a) 10 J
b) 20 J
c) 30 J
d) 40 J

Answer

Answer: a [Reason:] Change in the internal energy for a steady-state system is always zero so Q = W.

3. If x J of work is done on a steady system, what is the heat for the system?
a) + x J
b) –x J
c) 0 J
d) None of the mentioned

Answer

Answer: b [Reason:] Change in the internal energy for a steady-state system is always zero so Q + W= 0.

4. 10 J of heat is removed from a steady state system, what is the work done on the system?
a) – 10 J
b) 10 J
c) – 5 J
d) 5 J

Answer

Answer: b [Reason:] 0 = – 10 + W.

5. 25 J of work is done by a steady state system, what is the heat supplied to the system?
a) – 25 J
b) 25 J
c) 20 J
d) – 20 J

Answer

Answer: b [Reason:] 0 = – 15 + Q.

6. 20 J of heat is supplied to a system and a work of 30 J performed on it. If 50 J of heat is removed from the system, which type of system is it?
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: a [Reason:] ∆E = 0.

7. 10 J of heat is supplied to a system and a work of 30 J performed on it. If 50 J of heat is removed from the system, which type of system is it?
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: b [Reason:] ∆E is not equal to zero.

8. If 25 J is work is done on a system and same amount of heat is also supplied. What kind of system is it?
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: b [Reason:] ∆E is not equal to zero.

9. If 25 J is work is done by a system and same amount of heat is also supplied to the system. What kind of system is it?
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: a [Reason:] ∆E is equal to zero.

10. There must be no accumulation of mass or energy over the time period of interest in a _________
a) Steady state
b) Unsteady state
c) Closed
d) None of the mentioned

Answer

Answer: a [Reason:] There must be no accumulation of mass or energy over the time period of interest in a Steady state.

Set 5

1. A reaction for which heat must be added to the system to maintain isothermal condition is called
a) Endothermic Reaction
b) Exothermic Reaction
c) Neutral Reaction
d) None of the mentioned

Answer

Answer: a [Reason:] A reaction for which heat must be added to the system to maintain isothermal condition is called Endothermic Reaction.

2. A reaction for which heat must be removed from the system to maintain isothermal condition is called
a) Endothermic Reaction
b) Exothermic Reaction
c) Neutral Reaction
d) None of the mentioned

Answer

Answer: b [Reason:] A reaction for which heat must be removed from the system to maintain isothermal condition is called Exothermic Reaction.

3. Photosynthesis is _________
a) Exothermic
b) Endothermic
c) No heat transfer
d) None of the mentioned

Answer

Answer: b [Reason:] Photosynthesis is an Endothermic Reaction as heat is absorbed.

4. Electrolysis of water is
a) Exothermic
b) Endothermic
c) No heat transfer
d) None of the mentioned

Answer

Answer: b [Reason:] Photosynthesis is an Endothermic Reaction as heat is absorbed.

5. Burning Butane in a gas grill is
a) Exothermic
b) Endothermic
c) No heat transfer
d) None of the mentioned

Answer

Answer: a [Reason:] Combustion is an Exothermic Reaction as heat is released.

6. Rusting of Fe is
a) Exothermic
b) Endothermic
c) No heat transfer
d) None of the mentioned

Answer

Answer: a [Reason:] Combustion is an Exothermic Reaction as heat is released.

7. Burning is always an ______________ process.
a) Exothermic
b) Endothermic
c) No heat transfer
d) None of the mentioned

Answer

Answer: a [Reason:] Burning is an Exothermic Reaction as heat is released.

8. _________________ is always endothermic.
a) Burning
b) Freezing
c) Condensing
d) Boiling

Answer

Answer: d [Reason:] Boiling is an Endothermic Reaction as heat is absorbed.

9. Temperature for standard heat of formation is
a) 298 K
b) 300 K
c) 400 K
d) 528 K

Answer

Answer: a [Reason:] Standard temperature = 25 degree Celsius = 25+273 = 298 K.

10. Pressure for standard heat of formation is
a) 1 atm
b) 1 psi
c) 1 Kg/m2
d) None of the mentioned

Answer

Answer: a [Reason:] Standard pressure = 1 atm.