Explore topic-wise MCQs in Mechanical Engineering.

This section includes 11 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

Pure refrigerant vapour is obtained for the condenser in a vapour absorption cooling system:

A. By exchanging heat with the weak ammonia-water solution
B. Directly from the evaporator
C. By supplying the heat to the generator where ammonia gets released
D. By feeding from an external reservoir
Answer» D. By feeding from an external reservoir
2.

A refrigerant mostly used for the reciprocating compressor is

A. NH3
B. CO2
C. Freon - 12
D. Freon - 22
Answer» D. Freon - 22
3.

In the ammonia-water vapour absorption refrigeration cycle, the refrigerant used is:

A. water
B. brine
C. NH3
D. R-22
Answer» D. R-22
4.

Moisture in a refrigerant system is removed by _______.A. DriersB. Filter driersC. Desiccants

A. only A
B. only B
C. only C
D. A, B and C
Answer» E.
5.

Ideal refrigerant should not have :

A. positive pressure in evaporator
B. high latent heat of vaporisation
C. high thermal conductivity
D. high boiling temperature at atmospheric pressure
Answer» E.
6.

An undesirable property of a refrigerant is its:

A. low freezing point
B. low viscosity
C. high miscibility with lubricating oil
D. low latent heat of evaporation
Answer» E.
7.

In an Electrolux refrigerator

A. Ammonia is absorbed in water
B. Ammonia is absorbed in hydrogen
C. Hydrogen is evaporated in ammonia
D. Ammonia is evaporated in hydrogen
Answer» E.
8.

Fittings in ammonia absorption refrigeration system are made of _____.

A. Cast steel or forgings
B. Copper
C. Brass
D. Aluminium
Answer» B. Copper
9.

Modified polyol ester is a suitable lubricant in a refrigeration system with the refrigerant:

A. R-11
B. R-134a
C. R-245fa
D. R-12
Answer» C. R-245fa
10.

A mixture of refrigerants having a fixed boiling point is called:

A. Primary refrigerant
B. Brine
C. Secondary refrigerant
D. Azeotropic mixture
Answer» E.
11.

Lithium bromide in vapour absorption refrigeration system is used as _____.

A. refrigerant
B. cooling substance
C. auxiliary refrigerant
D. absorbent
Answer» E.