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
Correct Answer :
D. All of the above
Related Questions
Rankine Gordon formula for buckling is valid for
Long column
Short column
Short and long column
Very long column
For a shaft diameter of 100 mm, the number of bolts in a flange coupling should be
4
6
8
10
Factor of safety for fatigue loading is the ratio of
Elastic limit to the working stress
Elastic limit to the yield point
Endurance limit to the working stress
Young's modulus to the ultimate tensile strength
Wahl's stress factor __________ very rapidly as the spring index decreases.
Increases
Decreases
Remain same
None of these
If T is the actual number of teeth on a helical gear and φ is the helix angle for the teeth, then formative number of teeth is written as
T sec3φ
T sec²φ
T/sec3φ
T cosecφ
The stiffness of a closely coiled helical spring subjected to an axial load W is equal to (where G = Modulus of rigidity, and n = Number of active coils)
Gd⁴/ 8D3n
Gd3/ 8D3n
Gd⁴/ 4D3n
Gd⁴/ 8D²n
Cold working
Increases the fatigue strength
Decreases the fatigue strength
Has no influence on fatigue strength
Alone has no influence on fatigue strength
Which is positive drive?
Flat belt drive
V-belt drive
Crossed belt drive
Timing belt
For unequal width of butt straps, the thicknesses of butt straps are
0.75 t for narrow strap on the inside and 0.625 t for wide strap on the outside
0.75 t for wide strap on the inside and 0.625 t for narrow strap on the outside
0.75 t for both the straps on the inside and outside
0.625 t for both the straps on the inside and outside
For longitudinal joint in boilers, the type of joint used is
Butt joint with single cover plate
Butt joint with double cover plate
Lap joint with one ring overlapping the other
Any one of the above
Aircraft body is usually fabricated by
Welding
Pre-casting
Riveting
Casting
Tearing resistance required to tear off the plate per pitch length is (where p = Pitch of rivets, d = Dia. of rivet hole, and σt = Permissible tensile stress for plate material)
p.d.σt
p.t.σt
(p - d) σt
(p - d) t.σt
Which is correct statement? Stress concentration in static loading is
Very serious in brittle materials and less serious in ductile materials
Very serious in ductile materials and less serious in brittle materials
Equally serious in both types of materials
Seriousness would depend on other factors
The included angle for the V-belt is usually
10°-20°
30°-40°
40°-60°
60°-80°
A locking device extensively used in marine type connecting rod ends is a
Jam nut
Castle nut
Sawn nut
Ring nut
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 flat belt drive, if the slip between the driver and belt is 1 %, between the belt and follower is 3% and driver and follower pulley diameters are equal, then velocity ratio of the drive will be
0.96
0.97
0.98
0.99
When the belt speed increases
Power transmitted increases
Power transmitted decreases
Power transmitted increases to a maximum value and then decreases
Power transmitted remains the same
When a hole of diameter d is punched in a metal of thickness 't', then the force required to punch a hole is equal to (where τu = Ultimate shear strength of the material of the plate)
d.t.τu
πd.t.τu
π/4 × d².τu
π/4 × d² × t.τu
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
A spring is used to
Measure forces
Apply forces
Store energy
All of these
The design of the pressure vessel is based on
Longitudinal stress
Hoop stress
Longitudinal and hoop stress
None of these
The toughness of a material _________ when it is heated
Does not change
Increases
Decreases
None of the Above
A steel containing upto 0.15% carbon is known as
Mild steel
Dead mild steel
Medium carbon steel
High carbon steel
Which of the following property is essential for spring materials?
Stiffness
Ductility
Resilience
Plasticity
A column is known as a long column if the slenderness ratio is
40
50
70
100
Belt slip may occur due to
Heavy load
Loose belt
Driving pulley too small
All of the above
A locking device in which the bottom cylindrical portion is recessed to receive the tip of the locking set screw, is called
Ring nut
Castle nut
Sawn nut
Jam nut
When a beam of rectangular cross-section of width b and depth d, is subjected to a shear force F, the maximum shear stress induced will be
F/bh
3F/2bh
2F/bh
4F/bh
Which of the following statement is wrong?
A key is used as a temporary fastening
A key is subjected to tensile stresses
A key is always inserted parallel to the axis of the shaft
A key prevents relative motion between the shaft and boss of the pulley