Mechanical Engineering

Question: Moisture should be removed from refrigerants to avoid
[A].

freezing at the expansion valve

[B].

restriction to refrigerant flow

[C].

corrosion of steel plates

[D].

all of these

Answer: Option D

Explanation:

No answer description available for this question.

Question: Which of the following refrigerant has the maximum ozone depletion potential in the stratophere?
[A].

Ammonia

[B].

Carbon dioxide

[C].

Sulphur dioxide

[D].

Flourine

Answer: Option D

Explanation:

No answer description available for this question.

Question: Environmental protection agencies advice against the use of chloro-fluoro-carbon refrigerants since
[A].

these react with water vapour and cause acid rain

[B].

these react with plants and cause green-house effect

[C].

these react with oxygen and cause its depletion

[D].

these react with ozone layer

Answer: Option D

Explanation:

No answer description available for this question.

Question: In larger industrial and commercial reciprocating compression systems, refrigerent widely used is
[A].

ammonia

[B].

carbon dioxide

[C].

sulphur dioxide

[D].

R-12

Answer: Option A

Explanation:

No answer description available for this question.

Question: In absorption vapour systems, the refrigerant widely used is R-12.
[A].

Correct

[B].

Incorrect

Answer: Option B

Explanation:

No answer description available for this question.

Question: Carbon dioxide is
[A].

colourless

[B].

odourless

[C].

non-flammable

[D].

all of these

Answer: Option D

Explanation:

No answer description available for this question.

Question: Which of the following refrigerant is highly toxic and flammable?
[A].

Ammonia

[B].

Carbon dioxide

[C].

Sulphur dioxide

[D].

R-12

Answer: Option A

Explanation:

No answer description available for this question.

Question: Which of the following refrigerant has the highest freezing point.
[A].

Ammonia

[B].

Carbon dioxide

[C].

Sulphur dioxide

[D].

R-12

Answer: Option B

Explanation:

No answer description available for this question.

Question: Which of the following refrigerant has the lowest boiling point?
[A].

Ammonia

[B].

Carbon dioxide

[C].

Sulphur dioxide

[D].

R-12

Answer: Option B

Explanation:

No answer description available for this question.

Question: The boiling point of R-12 is about – 30°C.
[A].

True

[B].

False

Answer: Option A

Explanation:

No answer description available for this question.