Engineering :: Theory of Machines

@ : Home > Mechanical Engineering > Theory of Machines

141.

Which of the following instruments may be used in vibration measurements?

142.

In vibration analysis 'Beat' frequency is

A.	The frequency at which vibrations of a system are damped	B.	The frequency when a system exceeds the vibrations frequency from the critical value
C.	The frequency below which vibrations do not cause appreciable damage to equipment	D.	Said to occur when two vibrations of almost equal frequency are present
E.	One at which the vibrations of a system act exactly opposite to the other thereby causing damping

143.

A vibrometer

A.	Indicates vibration amplitude	B.	Indicates vibration frequency
C.	Indicates nature of vibrations	D.	Only indicates second and above harmonics
E.	Indicates wave from vibrations

144.

A vibrating system with unity as damping factor will be

145.

A 0.5 kg weight attached to a light spring elogates it 7.87 mm. The natural frequency of the system would be in the range

146.

In a system if the speed reduction of 60 : 1 is desired the convenient way is to use

147.

The type of teeth used on a gear used in sugar crushing is

148.

The vibrations in which the restoring forces are not proportional to the displacements and the first power of velocity are known as

149.

A vibrating system is said to be stable if

A.	The amplitude of vibration decreases with time	B.	The amplitude of vibration does not change with time
C.	Only transient increases indefinitely with time	D.	The total energy in the system does not change with time
E.	None of the above

150.

A stretched string of a guitar when operated is subjected to

A.	Free vibrations	B.	Forced torsional vibrations
C.	Forced transverse vibrations	D.	Damped vibrations
E.	None of the above