Mechanical Engineering

Question: If the number of pulleys in a system is equal to its velocity ratio, then it is a __________ system of pulleys
[A].

first

[B].

second

[C].

third

Answer: Option B

Explanation:

No answer description available for this question.

Question: For a self locking machine, the efficiency must be
[A].

equal to 50%

[B].

less than 50%

[C].

greater than 50%

[D].

100%

Answer: Option B

Explanation:

No answer description available for this question.

Question: A weight of 1000 N can be lifted by an effort of 80 N. If the velocity ratio is 20, the machine is
[A].

reversible

[B].

non-reversible

[C].

ideal

Answer: Option A

Explanation:

No answer description available for this question.

Question: A screw jack used for lifting the loads is
[A].

a reversible machine

[B].

a non-reversible machine

[C].

an ideal machine

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: A non-reversible machine is also called a self-locking machine.
[A].

Agree

[B].

Disagree

Answer: Option A

Explanation:

No answer description available for this question.

Question: A machine which is not capable of doing any work in the reversed direction, after the effort is removed, is called a reversible machine.
[A].

True

[B].

False

Answer: Option B

Explanation:

No answer description available for this question.

Question: If the resultant of two equal forces has the same magnitude as either of the forces, then the angle between the two forces is
[A].

30°

[B].

60°

[C].

90°

[D].

120°

Answer: Option D

Explanation:

No answer description available for this question.

Question: A machine which is capable of doing work in the reversed direction, after the effort is removed, is called a non-reversible machine.
[A].

Yes

[B].

No

Answer: Option B

Explanation:

No answer description available for this question.

Question: A machine having an efficiency greater than 50%, is known as
[A].

reversible machine

[B].

non-reversible machine

[C].

neither reversible nor non-reversible machine

[D].

ideal machine

Answer: Option A

Explanation:

No answer description available for this question.

Question: A machine having an efficiency less than 50%, is known as
[A].

reversible machine

[B].

non-reversible machine

[C].

neither reversible nor non-reversible machine

[D].

ideal machine

Answer: Option B

Explanation:

No answer description available for this question.