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51.

The type of governor used in record players for adjusting the speed of turn table generally is

52.

Idler pulley is used for

A.	Maintaining belt tension	B.	Changing direction of rotation
C.	For stopping motion frequently	D.	For running during idling periods only
E.	None of the above

53.

By using large thread angles in a lifting machine

A.	The mechanical advantage will be high	B.	The load will be sustained in absence of effort
C.	The mechanical advantage will be low	D.	The load will be easily lifted
E.	While unloading, little effort will be required

54.

Which is incorrect statement, if any

A.	The force of friction is independent of the velocity of sliding	B.	The force of friction is independent of the extent of the surfaces in contact
C.	The force of friction is directly proportional to the pressure between the surfaces in contact	D.	The laws of friction are true when the intensity of the pressure between the surfaces is small
E.	None of the above

55.

In a well greased ball bearing the coefficient of friction may be in the range

56.

The maximum efficiency of a screw jack provided with square threads and angle of friction 30? will be

57.

The purpose of providing multiple collars on a flat collar pivot bearing is to

A.	Increase frictional resistance	B.	To establish self-sustaining bearing condition
C.	Distribute the frictional load because of limiting friction	D.	Distribute the axial load because of limiting bearing pressure on a collar
E.	None of the above

58.

A belt drive is

A.	A positive drive	B.	Not a positive drive
C.	Meant for small torque transmission only	D.	Used only when the two pulleys have parallel axis
E.	None of the above

59.

Slip in belt drive is

A.	Loss of power	B.	Difference between the velocities of two pulleys
C.	Difference between the angular velocities of two pulleys	D.	Difference between the linear speed of the rim of pulley and the belt on it
E.	None of the above

60.

In case of flat belt drive the length of belt in case of

A.	Open belt depends on sum of the diameters of pulleys	B.	Open belts depends on difference of the diameters of pulleys
C.	Cross belts depends on the sum of the diameters of pulleys	D.	Cross belts depends on the difference of the diameters of pulleys
E.	None of the above