For high speed engines, the cam follower should move with
Uniform velocity
Simple harmonic motion
Uniform acceleration and retardation
Cycloidal motion
Correct Answer :
D. Cycloidal motion
Related Questions
The pitch of threads on a Jock nut in comparison to pitch of nut is
Same
Coarser
Finer
Very fine
The taper on a rectangular sunk key is
1 in 16
1 in 32
1 in 48
1 in 100
Wahl's stress factor __________ very rapidly as the spring index decreases.
Increases
Decreases
Remain same
None of these
A key made from a cylindrical disc having segmental cross-section, is known as
Woodruff key
Feather key
Flat saddle key
Gib head key
Pick up wrong statement. Fatigue strength can be increased by
Cold working
Shot peening
Grinding and lapping surface
Hot working
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
According to I.B.R., the factor of safety of riveted joint should not be less than
1
2
3
4
The objective of caulking in a riveted joint is to make the joint
Free from corrosion
Stronger in tension
Free from stress
Leak-proof
The resultant axial load on a bolt depends on
Initial tension
External load applied
Relative elastic yielding (springness) of the bolt and the connected member
All of the above
In a steam engine, the piston rod is usually connected to the crosshead by means of a
Knuckle joint
Cotter joint
Oldham coupling
Universal joint
Which of the following property is essential for spring materials?
Stiffness
Ductility
Resilience
Plasticity
Creep in belt is due to
Material of the belt
Material of the pulley
Uneven extensions and contractions due to varying tension
All of the above
The speed of the sprocket reduces as the chain pitch __________ for a given number of teeth.
Increases
Decreases
Remain same
None of these
The washer is generally specified by its
Outer diameter
Hole diameter
Thickness
Mean diameter
When the connected members are very yielding (soft gasket) as compared to the bolt, then the resultant load on the bolt will be equal to the
Initial tension
External load applied
Sum of the initial tension and external load applied
Initial tension or external load, whichever is greater
The endurance or fatigue limit is defined as the maximum value of the stress which a polished standard specimen can withstand without failure, for infinite number of cycles, when subjected to
Static load
Dynamic load
Static as well as dynamic load
Completely reversed load
Eulers formula for a mild steel column is not valid if the slenderness ratio is
90
60
120
100
The ball bearings are provided with a cage
To reduce friction
To facilitate slipping of balls
To prevent the lubricant from flowing out
To maintain the balls at a fixed distance apart
In block brakes, the ratio of shoe width to wheel diameter is taken between
0.1 and 0.25
0.25 and 0.50
0.50 and 0.75
0.75 and 1
Guest's theory of failure is applicable for following type of materials
Brittle
Ductile
Elastic
Plastic
The temperature at which the new grains are formed in the metal is known as
Lower critical temperature
Upper critical temperature
Recrystallisation temperature
None of these
Wire ropes as compared to cotton ropes
Are lighter in weight
Offer silent operation
Can withstand shock loads
All of these
The notch angle of the Izod impact test specimen is
10°
20°
30°
45°
If the tearing efficiency of a riveted joint is 75%, then the ratio of diameter of rivet to the pitch is equal to
0.2
0.25
0.50
0.6
A locking device extensively used in marine type connecting rod ends is a
Jam nut
Castle nut
Sawn nut
Ring nut
A plate with an elliptical hole in the centre, with semi-major axis (A) perpendicular to the direction of loading and semi-minor axis (b) along the direction of loading, is subjected to a pull P. The maximum stress induced at the edge of the hole is equal to (where σ = Stress for a plate with no hole i.e. nominal stress)
σ [1 + (b/2a)]
σ [1 + (2a/b)]
σ [1 + (b/3a)]
σ [1 + (3a/b)]
Cap screws are
Similar to small size tap bolts except that a greater variety of shapes of heads are available
Slotted for a screw driver and generally used with a nut
Used to prevent relative motion between parts
Provided with detachable caps
A single strap butt joint is always in __________ shear.
Single
Double
Triple share
None of these
Which of the following statement is correct?
A parallel sunk key is a taperless key
A parallel sunk key may be rectangular or square in cross-section
A flat saddle key is a taper key which fits in a key way of the hub and is flat on the shaft
All of the above
Gear box is used
To produce torque
For speed reduction
To obtain variable speeds
To increase efficiency of system