MCQ Questions and Answers on Dynamics of Machinery

Q.

The static balancing is satisfactory for low speed rotors but with increasing speeds, dynamic balancing becomes necessary. This is because the

A. unbalance couples are caused only at higher speeds

B. unbalance forces are no dangenrous at higher speeds

C. effect of unbalances are proportional to the square of the speed

D. effect of unbalances are directly proportional to the speed

Discuss

Answer : Option:- C

Explanation :

Discuss here! No Explaination Available for These Question.

Q.

When two rotors rotate in one direction and middle one rotates in opposite direction, then torsional vibration occurs with

A. Four nodes

B. Three nodes

C. Two Nodes

D. Single node

Discuss

Answer : Option:- C

Explanation :

Discuss here! No Explaination Available for These Question.

Q.

One of the methods of vibration control is, controlling the natural frequencies of the system and ______ under excitation.

A. Introducing a damping

B. Use of vibration isolator

C. addition of vibration absorber

D. avoiding resonance

Discuss

Answer : Option:- D

Explanation :

Discuss here! No Explaination Available for These Question.

Q.

Magnification factor is defined as the ratio of

A. Steady state amplitude and static deflection of spring

B. Steady state amplitude and zero frequency amplitude

C. Both options (1) and (2)

D. Force transmitted to support and inertia force

Discuss

Answer : Option:- B

Explanation :

Discuss here! No Explaination Available for These Question.

Q.

The balancing weights are introduced in planes parallel to the plane of rotation of the disturbing mass. To obtain complete dynamic balance, the minimum number of balancing weights to be introduced in different planes is

A. one

B. two

C. three

D. four

Discuss

Answer : Option:- B

Explanation :

Discuss here! No Explaination Available for These Question.

Q.

For the free torsional vibration of a geared system which of the following statement is true?

A. Backlash in geared system

B. High inertia of shaft

C. Gearing teeth always in contact

D. High inertia of gear

Discuss

Answer : Option:- C

Explanation :

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Q.

Vibration can be eliminated on the basis of theoretical analysis

A. never

B. always

C. sometimes

D. Can't say

Discuss

Answer : Option:- C

Explanation :

Discuss here! No Explaination Available for These Question.

Q.

In vibration isolation system, if ω/ωn < 2, then for all values of damping factor, the transmissibility will be

A. less than unity

B. equal to unity

C. greater than unity

D. zero

Discuss

Answer : Option:- C

Explanation :

Discuss here! No Explaination Available for These Question.

Q.

In the spring mass system if the mass of the system is doubled with spring stiffness stiffness halved, the natural frequency of longitudinal vibration

A. remained unchanged

B. is doubled

C. is halved

D. is quadrupled

Discuss

Answer : Option:- C

Explanation :

Natural frequency of spring given by,
ωn = √(k/m)
Putting given value, in above equation we can observe that natural frequency get halved.

Q.

In case of a system with reciprocating unbalance, the nature of excitation force is

A. Approximately harmonic at low speed

B. Constant

C. Aperiodic or non-periodic

D. Uncertain or random

Discuss

Answer : Option:- A

Explanation :

Discuss here! No Explaination Available for These Question.

MCQ Questions and Answers on Dynamics of Machinery

Q. The static balancing is satisfactory for low speed rotors but with increasing speeds, dynamic balancing becomes necessary. This is because the

Q. When two rotors rotate in one direction and middle one rotates in opposite direction, then torsional vibration occurs with

Q. One of the methods of vibration control is, controlling the natural frequencies of the system and ______ under excitation.

Q. Magnification factor is defined as the ratio of

Q. The balancing weights are introduced in planes parallel to the plane of rotation of the disturbing mass. To obtain complete dynamic balance, the minimum number of balancing weights to be introduced in different planes is

Q. For the free torsional vibration of a geared system which of the following statement is true?

Q. Vibration can be eliminated on the basis of theoretical analysis

Q. In vibration isolation system, if ω/ωn < 2, then for all values of damping factor, the transmissibility will be

Q. In the spring mass system if the mass of the system is doubled with spring stiffness stiffness halved, the natural frequency of longitudinal vibration

Q. In case of a system with reciprocating unbalance, the nature of excitation force is

Q.

The static balancing is satisfactory for low speed rotors but with increasing speeds, dynamic balancing becomes necessary. This is because the

Q.

When two rotors rotate in one direction and middle one rotates in opposite direction, then torsional vibration occurs with

Q.

One of the methods of vibration control is, controlling the natural frequencies of the system and ______ under excitation.

Q.

Magnification factor is defined as the ratio of

Q.

The balancing weights are introduced in planes parallel to the plane of rotation of the disturbing mass. To obtain complete dynamic balance, the minimum number of balancing weights to be introduced in different planes is

Q.

For the free torsional vibration of a geared system which of the following statement is true?

Q.

Vibration can be eliminated on the basis of theoretical analysis

Q.

In vibration isolation system, if ω/ωn < 2, then for all values of damping factor, the transmissibility will be

Q.

In the spring mass system if the mass of the system is doubled with spring stiffness stiffness halved, the natural frequency of longitudinal vibration

Q.

In case of a system with reciprocating unbalance, the nature of excitation force is