In most machine members, the damping capacity of the material should be
Low
Zero
High
Could be anything
Correct Answer :
C. High
Related Questions
According to I.B.R., the factor of safety of riveted joint should not be less than
1
2
3
4
When compared to the rod of the same diameter and material, a wire rope
Is less flexible
Has a much smaller load carrying capacity
Does not provide much warning before failure
Provides much greater time for remedial action before failure
When a nut is tightened by placing a washer below it, the bolt will be subjected to following type of loads
Compression
Tension
Shear
Combined loads
Screws used for power transmission should have
Very fine threads
High efficiency
Low efficiency
Strong teeth
When an open coiled helical compression spring is subjected to an axial compressive load, the stress induced in the wire is
Tensile stress
Compressive stress
Shear stress
Bending stress
Which of the following key is preferred for the condition when a large amount of impact type torque is to be transmitted in both direction of rotation?
Woodruff key
Feather key
Gib-head key
Tangent key
Which of the following statement is wrong?
The pitch of rivets is obtained by equating the tearing resistance of the plate to the shearing resistance of the rivets
The pitch of rivets should not be less than 2d, where d is the diameter of rivet hole
The maximum value of the pitch of rivets for a longitudinal joint of a boiler, as per I.B.R., is given by Pmax = C.t + 41.28 mm
According to I.B.R., the thickness of butt strap shall not be less than 5 mm
A single strap butt joint is always in __________ shear.
Single
Double
Triple share
None of these
The shear stress in a beam varies from zero at the outer fibres to a maximum at the________.
Neutral surface
Upper surface
Lower surface
None of these
Which of the following statement is correct regarding power screws?
The efficiency of a self locking screw can not be more than 50%
The efficiency of Acme (trapezoidal) thread is less than that of a square thread
If the friction angle is less than the helix angle of the screw, then the efficiency will be more than 50%
(A) and (B) Only
In designing a connecting rod, it is considered like __________ for buckling about X-axis.
Both ends hinged
Both ends fixed
One end fixed and the other end hinged
One end fixed and the other end free
In thrust bearings, the load acts
Along the axis of rotation
Parallel to the axis of rotation
Perpendicular to the axis of rotation
In any direction
The application of third type levers is found in
A pair of tongs
Hand wheel of a punching press
Lever of a loaded safety valve
Handle of a hand pump
A fast and loose pulley drive is used when
Shafts are arranged parallel and rotate in the opposite directions
Shafts are arranged parallel and rotate in the same directions
Shafts are arranged at right angles and rotate in one definite direction
Driven shaft is to be started or stopped whenever desired without interfering with the driving shaft
The efficiency of a riveted joint is equal to
Pt /P
Ps /P
Pc /P
Least of Pt, Ps and Pc/P
In radial bearings, the load acts __________ to the axis of rotation.
Parallel
Perpendicular
Both A and B
None of these
The edges of the plates for cylindrical vessels are usually bevelled to an angle of 80° for
Reducing stress concentration
Ease of manufacture
Safety
Fullering and caulking
When screw threads are to be used in a situation where power is being transmitted in one direction only, then the screw threads suitable for this will be
Knuckle threads
Square threads
Acme threads
Buttress threads
A machine part subjected to __________ is called a strut.
An axial compressive force
A tangential force
An axial tensile force
Any one of these
In worm, gears, pitch lead angle is
Half the angle between two inclined faces in axial plane
The angle between the tangent to the pitch helix and the plane of rotation
The angle between the tangent to the pitch helix and an element of the cylinder
None of the above
Idler pulley is used for
Increasing velocity ratio
For applying tension
Changing the direction of motion of belt
All of these
For general industrial machinery, the ratio of the length of journal to its diameter is taken as
0.5 to 1
1 to 2
3 to 5
5 to 10
Oldham coupling is used to connect two shafts
Which are perfectly aligned
Which are not in exact alignment
Which have lateral misalignment
Whose axes intersect at a small angle
When bevel gears having equal teeth and equal pitch angles connect two shafts whose axes intersect at right angle, then they are known as
Angular bevel gears
Crown bevel gears
Internal bevel gears
Mitre gears
The ratio of the ultimate stress to the design stress is known as
Elastic limit
Strain
Factor of safety
Bulk modulus
The expression 0.175 - 0.841/T is the Lewis form factor for
14 ½° composite and full depth involute system
20° full depth involute system
20° stub system
None of the above
A column of length l is fixed at both ends. The equivalent length of the column is
l/2
l/√2
l
2 l
The connecting rod bolts are tightened up so that tightening stress
Is just sufficient to hold parts together
Approaches yield point
Is 50% of yield point
Is about yield point divided by safety factor
The wire ropes make contact at
Bottom of groove of the pulley
Sides and bottom of groove of the pulley
Anywhere in the groove of the pulley
Sides of groove of the pulley
The included angle between the sides of V-belt is
40°
45°
38°
60°