Explore topic-wise MCQs in Thermodynamics.

This section includes 15 Mcqs, each offering curated multiple-choice questions to sharpen your Thermodynamics knowledge and support exam preparation. Choose a topic below to get started.

1.

IN_THE_EXPANSION_PROCESS,_WHICH_OF_THE_FOLLOWING_REMAINS_CONSTANT??$

A. work done
B. heat supplied
C. internal energy
D. enthalpy
Answer» E.
2.

One tonne of refrigeration is given as the rate of heat removal from surroundings equivalent to heat required for melting one tonne of ice in a day.$

A. true
B. false
Answer» B. false
3.

The COP of cycle is given by(Q2=heat absorbed by evaporator and Wc=work done by compressor)$

A. 1- (Q2/Wc)
B. 1- (Wc/Q2)
C. Q2/Wc
D. Wc/Q2
Answer» D. Wc/Q2
4.

A condenser must ____ and then ____ the compressed refrigerant.

A. superheat, evaporate
B. desuperheat, evaporate
C. superheat, condense
D. desuperheat, condense
Answer» E.
5.

Superheating of vapour and subcooling of liquid ____ the refrigerating effect.

A. decreases
B. increases
C. no change
D. none of the mentioned
Answer» C. no change
6.

Which of the following is recommended in a refrigeration cycle?

A. superheating of vapour
B. subcooling of liquid
C. both of the mentioned
D. none of the mentioned
Answer» D. none of the mentioned
7.

The evaporator produces the cooling or refrigerating effect?

A. true
B. false
Answer» B. false
8.

The evaporation process is a

A. constant volume reversible process
B. constant pressure reversible process
C. adiabatic throttling process
D. reversible adiabatic process
Answer» C. adiabatic throttling process
9.

The expansion process is

A. isentropic
B. reversible
C. adiabatic
D. all of the mentioned
Answer» D. all of the mentioned
10.

In the cooling and condensing, correct sequence of processes is

A. desuperheated->condensed->saturated liquid
B. desuperheated->saturated liquid->condensed
C. condensed->desuperheated->saturated liquid
D. saturated liquid->condensed->desuperheated
Answer» B. desuperheated->saturated liquid->condensed
11.

Why is wet compression not preferred?

A. the liquid refrigerant can be trapped in the head of cylinder
B. this may damage the valves or cylinder head
C. liquid refrigerant can wash away the lubricating oil thus accelerating wear
D. all of the mentioned
Answer» E.
12.

Wet compression is preferred over dry compression.

A. true
B. false
Answer» C.
13.

Compression can be

A. dry compression
B. wet compression
C. both of the mentioned
D. none of the mentioned
Answer» D. none of the mentioned
14.

Which of the following operations occur in a vapour refrigeration cycle?

A. compression
B. cooling and condensing
C. expansion and evaporation
D. all of the mentioned
Answer» E.
15.

In vapour refrigeration cycle, which of the following is used for expansion?

A. expansion engine
B. throttling valve or capillary tube
C. both of the mentioned
D. none of the mentioned
Answer» C. both of the mentioned