Mechanical Engineering

Question: If the net positive suction head (NPSH) requirement for the pump is not satisfied, then
[A].

no flow will take place

[B].

cavitation will be formed

[C].

efficiency will be low

[D].

excessive power will be consumed

Answer: Option B

Explanation:

No answer description available for this question.

Question: For centrifugal pump impeller, the maximum value of the vane exit angle is
[A].

10° to 15°

[B].

15° to 20°

[C].

20° to 25°

[D].

25° to 30°

Answer: Option C

Explanation:

No answer description available for this question.

Question: Delivery head of water of a centrifugal pump is inversely proportional to diameter of its impeller.
[A].

Yes

[B].

No

Answer: Option B

Explanation:

No answer description available for this question.

Question: Discharge of a centrifugal pump is
[A].

directly proportional to diameter of its impeller

[B].

inversely proportional to diameter of its impeller

[C].

directly proportional to (diameter)2 of its impeller

[D].

inversely proportional to (diameter)2 of its impeller

Answer: Option C

Explanation:

Discharge of a centrifugal pump is directly proportional to (Diameter)^2 of its impeller.

Head of a centrifugal pump is directly proportional to (Diameter)^2 of its impeller.

Power Developed of a centrifugal pump is directly proportional to (Diameter)^4 of its impeller.

Question: Delivery head of a centrifugal pump is
[A].

directly proportional to N

[B].

inversely proportional to N

[C].

directly proportional to N2

[D].

inversely proportional to N2

Answer: Option C

Explanation:

No answer description available for this question.

Question: Discharge of a centrifugal pump is (where N = Speed of the pump impeller)
[A].

directly proportional to N

[B].

inversely proportional to N

[C].

directly proportional to N2

[D].

inversely proportional to N2

Answer: Option A

Explanation:

No answer description available for this question.

Question: By fitting an air vessel to the reciprocating pump, there is always a saving of work done and subsequently saving of power.The saving in case of a double acting reciprocating pump is
[A].

39.2%

[B].

48.8%

[C].

84.8%

[D].

88.4%

Answer: Option A

Explanation:

No answer description available for this question.

Question: By fitting an air vessel to the reciprocating pump, there is always a saving of work done and subsequently saving of power. This saving in case of a single acting reciprocating pump is
[A].

39.2%

[B].

48, 8%

[C].

84.8%

[D].

88.4%

Answer: Option C

Explanation:

No answer description available for this question.

Question: In a reciprocating pump, air vessels are used to
[A].

smoothen the flow

[B].

reduce suction head

[C].

increase delivery head

[D].

reduce acceleration head

Answer: Option D

Explanation:

No answer description available for this question.

Question: In a reciprocating pump, air vessels are fitted to the suction pipe and delivery pipe close to the cylinder of the pump.
[A].

True

[B].

False

Answer: Option A

Explanation:

No answer description available for this question.