Spring stiffness is
Ratio of coil diameter to wire diameter
Load required to produce unit deflection
Its capability of storing energy
Its ability to absorb shocks
Correct Answer :
B. Load required to produce unit deflection
Related Questions
The shock absorbing capacity of a bolt may be increased by
Increasing its shank diameter
Decreasing its shank diameter
Tightening the bolt properly
Making the shank diameter equal to core diameter of thread
The size of a cam depends upon
Base circle
Pitch circle
Prime circle
Pitch curve
Crowning on pulley helps
In decreasing the slip of the belt
In increasing the slip of the belt
To keep the belt in centre on a pulley while it is in motion
To increase pulley life
The load cup of a screw jack is made separate from the head of the spindle to
Prevent the rotation of load being lifted
Enhance the load carrying capacity of the jack
Reduce the effort needed for lifting the working load
Reduce the value of frictional torque
In case of pressure vessels having closed ends, the fluid pressure induces
Longitudinal stress
Shear stress
Circumferential stress
None of these
In a marine flange coupling, the thickness of flange is taken as
d/2
d/3
3d/4
d/4
The maximum stress due to stress concentration in a bar having circular transverse hole, as compared to its static stress without hole will be
Same in both cases
2 times more
3 times more
4 times more
Stress concentration in cyclic loading is more serious in
Ductile materials
Brittle materials
Equally serious in both cases
Depends on other factors
The cracks in helical springs used in railway carriages usually start on the inner side of the coil because of the fact that
It is subjected to a higher cyclic loading than the outer side
It is subjected to a higher stress than the outer side
It is more stretched than the outer side during the manufacturing process
It has a lower curvature than the outer side
Which of the following cotter joint will be used to connect strap end of a connecting rod?
Spigot and socket cotter joint
Sleeve and cotter joint
Gib and cotter joint
Any one of these
Two shafts will have equal strength, if
Diameter of both the shafts is same
Angle of twist of both the shafts is same
Material of both the shafts is same
Twisting moment of both the shafts is same
Oil in journal bearing should be applied at the point where load is
Nil or lightest
Maximum
Average
Any one of the above
The process which improves the machinability of steels, but lowers the hardness and tensile strength is
Normalising
Full annealing
Process annealing
Spheroidising
In nitrated parts, the origins of the fatigue cracks will occur at
Surface
Just below the surface
Within the core
None of the above
Buttress threads are usually found on
Screw cutting lathes
Feed mechanisms
Spindles of bench vices
Railway carriage couplings
The material generally used for aircraft components is
Mild steel
High speed steel
Stainless steel
Aluminium
The contact ratio is the ratio of
Length of arc of recess to the circular pitch
Length of path of contact to the circular pitch
Length of arc of contact to the circular pitch
Length of arc of approach to the circular pitch
At low temperatures (say 75°C) the notched bar impact value of steel
Increases markedly
Decreases markedly
Remain same
Depends on heat treatment carried out
If a bearing is designated by the number 305, it means that the bearing is of
Medium series whose bore is 5 mm
Medium series whose bore is 25 mm
Light series whose bore is 25 mm
Light series whose bore is 5 mm
The minimum number of teeth on the pinion which will mesh with any gear without interference for 20° full depth involute teeth will be
12
14
18
24
According to I.B.R., the factor of safety of riveted joint should not be less than
1
2
3
4
The form factor of a helical gear __________ with the increase in the helix angle.
Increases
Decreases
Remains constant
None of these
The velocity factor for very accurately cut and ground metallic gears operating at velocities upto __________ are equal to 6/(6 + v).
10 m/s
12.5 m/s
15 m/s
20 m/s
In a belt drive, if the pulley diameter is doubled keeping the tension and belt width constant, then it will be necessary to
Increase the key length
Increase the key depth
Increase the key width
Decrease the key length
Shear stress theory is applicable for
Ductile materials
Brittle materials
Elastic materials
All of the above
The steel pulleys are __________ in weight than cast iron pulleys of the same capacity.
Heavier
Lighter
Moderate
None of these
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
In designing a key, it is assumed that the distribution of forces along the length of key
Varies linearly
Is uniform throughout
Varies exponentially, being more at the torque-input end
Varies exponentially, being less at the torque-input end
The fatigue life of a part can be improved by
Electroplating
Polishing
Coating
Shot peening
Aircraft body is usually fabricated by
Welding
Pre-casting
Riveting
Casting