Mechanical Engineering - Theory of machines

16. 

In vibration isolation system, the transmissibility will be equal to unity, for all values of damping factor, if ω/ωn is

A. equal to one
B. equal to 2
C. less than 2
D. greater than 2

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.

17. 

The two links OA and OB are connected by a pin joint at O. If the link OA turns with angular velocity ω1 rad/s in the clockwise direction and the link OB turns with angular velocity ω2 rad/s in the clockwise direction, then the rubbing velocity at the pin joint O is (where r = Radius of the pin at O)

A. ω12.r
B. ( ω1 - ω2)r
C. ( ω1 + ω2)r
D. ( ω1 - ω2)2r

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.

18. 

If ω/ωn = 2, where co is the frequency of excitation and ωn is the natural frequency of vibrations, then the transmissibility of vibration will the

A. 0.5
B. 1
C. 1.5
D. 2

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.

19. 

A disturbing mass m1 attached to the rotating shaft may be balanced by a single mass m2 attached in the same plane of rotation as that of m1, such that (where r1 and r2 are the radii of rotation of m1 and m2 respectively)

A. m1r2 = m2r1
B. m1r1 = m2r2
C. m1m2 = r1r2
D. none of these

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.

20. 

In railway axle boxes, the bearing used is

A. deep groove ball bearing
B. double row self-aligning ball bearing
C. double row spherical roller bearing
D. cylindrical roller bearing

Answer: Option C

Explanation:

No answer description available for this question. Let us discuss.