Dynamics of Machinery (3151911) MCQs

MCQs of Free vibrations and damped free vibrations

Showing 61 to 70 out of 88 Questions
61.

Logarithmic decrement is defined as the ____________ of the amplitude reduction factor.

(a)

reciprocal

(b)

logarithm

(c)

natural logarithm

(d)

equal

Answer:

Option (c)

62.

In damped vibrations, the amplitude of the resulting vibration gradually reduces. This is due to the reason that an amount of energy is always dissipated to overcome the ________.

(a)

frictional resistance

(b)

work done

(c)

fluid pressure

(d)

air pressure

Answer:

Option (a)

63.

An increase in the modulus of rigidity results in ________ in vibration frequency.

(a)

increase

(b)

decrease

(c)

unchanged

(d)

not fixed

Answer:

Option (a)

64.

An increase in the length of the shaft results in ________ in vibration frequency.

(a)

increase

(b)

decrease

(c)

unchanged

(d)

not fixed

Answer:

Option (b)

65.

An increase in the mass moment of inertia results in ________ in vibration frequency.

(a)

increase

(b)

decrease

(c)

unchanged

(d)

not fixed

Answer:

Option (b)

66.

If the mass moment of inertia is increased to four times, then what will be the effect on free torsional vibrations of a single motor system?

(a)

Increases 4 times

(b)

Increases 2 times

(c)

Decreases 4 times

(d)

Decreases 2 times

Answer:

Option (d)

67.

An increase in the polar moment of inertia results in ________ in vibration frequency.

(a)

increase

(b)

decrease

(c)

unchanged

(d)

not fixed

Answer:

Option (a)

68.

If the polar moment of inertia is increased to four times, then what will be the effect on free torsional vibrations of a single motor system?

(a)

Increases 4 times

(b)

Increases 2 times

(c)

Decreases 4 times

(d)

Decreases 2 times

Answer:

Option (b)

69.

Which of the following relation is correct regarding free torsional vibrations of a single motor system?

(a)

Independent of modulus of rigidity

(b)

Independent of polar moment of inertia

(c)

Dependent on the mass moment of inertia

(d)

Independent of the length of the shaft

Answer:

Option (c)

70.

At a nodal point in a shaft, the amplitude of torsional vibration is ___________ .

(a)

zero

(b)

minimum

(c)

maximum

(d)

negative

Answer:

Option (a)

Showing 61 to 70 out of 88 Questions