34.

35.

36.

87.

38.

Which of the following statements is/are true about contact ratio?
@ ‘It measures the average number of teeth in contact during meshing
(11) Contact ratio is always maintained at one
(011) A lower contact ratio necessitates a higher degree of accuracy in machining
(iv) The angle of action must be greater than pitch angle
(^) (Qi, Gii) and (iv) only (8). (0), (01) and (iii) only
(0) @ and (ii) only ) only

Which of the following statements is/are true about velocity ratio of worm gear drives?
டு Velocity ratio is the ratio of diameter of the worm wheel to the diameter of the worm

(i) Velocity ratio is the ratio of number of teeth on the wheel to the number of teeth on the
worm

(111) Velocity ratio is the ratio of the number of teeth on the worm wheel to the number of
starts on the worm

(iv) Velocity ratio is the ratio of speed of worm to the speed of worm wheel

(^) @ and (ii) only (B) (i) and (iii) only
(C) (ii) and (iv) only (9) (0 and (iv) only
The energy dissipated in viscous damping is proportional to :
(A) The amplitude (B) Square of the amplitude
(C) Cube of the amplitude (D) 2 power of the amplitude

Which of the following statements is/are true with respect to Coulomb damping?
@ Damping force is constant
Gi) Damping force is independent of relative velocity
Gii) Damped natural frequency of vibration is same as undamped natural frequency
(iv) Loss of amplitude per cycle is four times the ratio of frictional force to stiffness
(A) @, Gi) and (iii) only
൯ (ii), Gil) and (iv) only
(C) i) and (iii) only
൯൬) 0, (10, (11 and (iv)
A cantilever beam of length L, moment of inertia I, and modulus of Elasticity E, carries a

mass m, at its free end. What is the natural frequency of transverse vibrations neglecting the
beam mass?

(= (=
۸
‏م كل م‎ 2
ட (=
0
ര ०)
9 121/2022

[P.T.0.]