The stress induced in the belt is,
Tensile stress
Compressive stress
Direct shear stress
Torsional shear stress
Correct Answer :
A. Tensile stress
Related Questions
A thin spherical shell of internal diameter d is subjected to an internal pressure p. If V is the storage capacity of shell, then its diameter will be
(6V/ π)1/2
(6V/ π)1/3
(6V/ π)2
(6V/ π)3
A connecting rod should be
Strong in buckling about X-axis
Strong in buckling about Y-axis
Equally strong in buckling about X-axis and Y-axis
Any one of the above
In V-belt drive, belt touches
At bottom
At sides only
Both at bottom and sides
Could touch anywhere
Which of the following coupling is used to connect two shafts which have both lateral and angular misalignment?
Bushed pin type coupling
Universal coupling
Oldham coupling
All of these
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
If the centre distance of the mating gears having involute teeth is increased, then the pressure angle
Increases
Decreases
Remains unchanged
None of these
The endurance limit in shear of carbon steel can be obtained by multiplying the endurance limit in flexure by a factor of
0.45
0.55
0.65
0.75
According to maximum shear stress theory, the maximum shear stress in the shaft is
(1/2) × √(σ² + 4τ²)
√(σ² + 4τ²)
(1/2) × [σ + √(σ² + 4τ²)]
σ + √(σ² + 4τ²)
The included angle for the British Association thread is
29°
55°
47.3°
60°
In radial cams, the follower moves
In a direction parallel to the cam axis
In a direction perpendicular to the cam axis
In any direction irrespective of cam axis
Along the cam axis
A key made from a cylindrical disc having segmental cross-section, is known as
Woodruff key
Feather key
Flat saddle key
Gib head key
Silver based solder is used for
Flaring
Brazing
Soft soldering
Fusion welding
A transmission shaft includes
Over head shaft
Counter shaft
Line shaft
All of these
The pitch diameter is the __________ diameter of an external or internal screw thread.
Effective
Smallest
Largest
None of these
I.S. specifies following total number of grades of tolerances
18
16
20
22
In hydrodynamic bearings
The oil film pressure is generated only by the rotation of the journal
The oil film is maintained by supplying oil under pressure
Do not require external supply of lubricant
Grease is used for lubrication
The ratio of the ultimate stress to the design stress is known as
Elastic limit
Strain
Factor of safety
Bulk modulus
Eulers formula for a mild steel column is not valid if the slenderness ratio is
90
60
120
100
According to I.B.R., shearing resistance required to shear off the rivet per pitch length (in double shear) is (where n = Number of rivets per pitch length)
(π/4) d² × τ × n
1.875 × (π/4) d² × τ × n
2 × (π/4) d² × τ × n
3 × (π/4) d² × τ × n
For a square key made of mild steel, the shear and crushing strength are related as
Shear strength is equal to crushing strength
Shear strength is greater than crushing strength
Shear strength is less than crushing strength
None of the above
The ratio of driving tensions for flat belts, neglecting centrifugal tension, is (where T₁, and T₂ = Tensions on the tight and slack sides of belt respectively, μ = Coefficient of friction, between the belt and pulley, and θ = Angle of contact)
T₁/T₂ = μθ
log (T₁/T₂) = μθ
T₁/T₂ =eμθ
T₁/T₂ = log μθ
The permissible stress in the fillet weld is 100 N/mm². The fillet weld has equal leg lengths of 15 mm each. The allowable shearing load on the weldment per cm length of the weld is
7.5 kN
10.6 kN
15 kN
22.5 kN
A machine part subjected to __________ is called a strut.
An axial compressive force
A tangential force
An axial tensile force
Any one of these
Turn buckle has
Right hand threads on bout ends
Left hand threads on both ends
Left hand threads on one end and right hand threads on other end
No threads
The condition for maximum power transmission is that the maximum tension in the flat belt should be equal to
3 Pc
Pc
Pc/3
2 Pc Where, Pc = tension in belt due to centrifugal force
Deep groove ball bearings are used for
Heavy thrust load only
Small angular displacement of shafts
Radial load at high speed
Combined thrust and radial loads at high speed
In the calculation of induced shear stress in helical springs, the Wahl's stress factor is used to take care of
Combined effect of transverse shear stress and bending stress in the wire
Combined effect of bending stress and curvature of the wire
Combined effect of transverse shear stress and curvature of wire
Combined effect of torsional shear stress and transverse shear stress in the wire
In a band and block brake, the ratio of tensions on the tight and slack sides of band is given by (where μ = Coefficient of friction between the blocks and the drum, θ = Semi-angle of each block subtending at the centre of drum, and n = Number of blocks)
T₁/T₂ = μθ × n
T₁/T₂ = (μθ)n
T₁/T₂ = [(1 - μ tanθ)/ (1 + μ tanθ)]n
T₁/T₂ = [(1 + μ tanθ)/ (1 - μ tanθ)]n
Soderberg relation is based on __________ of the material whereas all other failure relation for dynamic loading are based on ultimate strength of the material.
Elastic strength
Yield strength
Shear strength
None of these
According to I.B.R., when the thickness of the boiler shell (t) is less than 8 mm, then the diameter of the rivet hole (d) is obtained by
Equating tearing resistance of the plate to the shearing resistance of the rivets
Equating tearing resistance of the plate to the crushing resistance of the rivets
Equating shearing resistance to the crushing resistance of the rivets
None of the above