Applied Thermodynamics (3161910) MCQs

MCQs of Refrigerant and Refrigeration Cycles

Showing 51 to 60 out of 65 Questions
51.
The COP of the VAR system is _________ compared to the COP of the VCR system.
(a) high
(b) less
(c) same
(d) depends on the capacity of the plant
Answer:

Option (b)

52.

Why intercooling by liquid refrigerant never used in R-12 systems?

(a)

High latent heat of vaporization

(b)

Low latent heat of vaporization

(c)

Medium latent heat of vaporization

(d)

High toxicity

Answer:

Option (b)

53.

The refrigeration effect produced by a system is 10 TR and work done by the low-pressure compressor, and high-pressure compressor is 3 and 4 kW respectively. What is the value of C.O.P. for the given conditions?

(a)

8.75

(b)

11.67

(c)

3.5

(d)

5

Answer:

Option (d)

54.

Why multi-stage or compound VCR with intercooler is used?

(a)

To improve C.O.P.

(b)

To decrease the refrigeration effect

(c)

To increase work

(d)

To increase leakage loss

Answer:

Option (a)

55.

What does process 1-2 and 3-4 represent?

(a)

Evaporation

(b)

Compression

(c)

Condensation

(d)

Expansion

Answer:

Option (b)

56.

What does process 2-3 represent?

(a)

Evaporation

(b)

Compression

(c)

Condensation

(d)

Intercooling

Answer:

Option (d)

57.

What is the relation between m1, m2, and m3?

refrigeration-questions-answers-two-multi-stage-compression-liquid-intercooling-2-q6

If m1 = mass of refrigerant passing through the evaporator
m2 = mass of refrigerant passing through the intercooler
m3 = mass of liquid evaporated in the condenser

(a)

m3=m1+m2

(b)

m3=m1-m2

(c)

m3=m2-m1

(d)

m3=m1/m2

Answer:

Option (a)

58.

What type of compound vapor compression is the following diagram of?

(a)

Two stage vapor compression with liquid intercooler

(b)

Three stage vapor compression with water intercooler and liquid subcooler

(c)

Two stage vapor compression with flash intercooler

(d)

Two stage vapor compression with water intercooler and liquid subcooler

Answer:

Option (d)

59.

A compound vapor compression with a liquid subcooler and a liquid intercooler system is used to take 10 TR of refrigeration load (Q). The power required for the refrigerating system P is 557.7 W. What is its COP?

(a)

6.87

(b)

4.75

(c)

3.77

(d)

5.86

Answer:

Option (c)

60.

What is the purpose of using intercooler?

(a)

To increase the cost of the compressor

(b)

To reduce the volumetric efficiency

(c)

To re-heat superheated refrigerant

(d)

To cool the superheated refrigerant

Answer:

Option (d)

Showing 51 to 60 out of 65 Questions