Straining
Fatigue
Creep
Sudden loading
B. Fatigue
Equal to
Less than
Greater than
None of these
Bottom side of belt as slack side
Top side of belt as slack side
Idler pulley
None of the above
Both sides of the actual size
One side of the actual size
One side of the nominal size
Both sides of the nominal size
The distance from a point on one thread to the corresponding point on the next thread is called pitch
The distance which a screw thread advances axially in one rotation of the nut is called lead
In single start threads, lead is equal to pitch
All of the above
√2P/s.l
P/2.s.l
P/√2.s.l
2P/s.l
Are lighter in weight
Offer silent operation
Can withstand shock loads
All of these
8
12
18
20
Normal pitch
Axial pitch
Diametral pitch
Module
Directly proportional to (shaft diameter)²
Inversely proportional to (shaft diameter)²
Directly proportional to (shaft diameter)⁴
Inversely proportional to (shaft diameter)⁴
Shafts are arranged at right angles and rotate in one definite direction
Shafts are arranged parallel and rotate in the opposite directions
Shafts are arranged parallel and rotate in the same directions
Driven shaft is to be started or stopped whenever desired without interfering with the driving shaft
Regains its original shape after deformation when the external forces are removed
Draw into wires by the application of a tensile force
Resists fracture due to high impact loads
Retain deformation produced under load permanently
Heavier
Lighter
Moderate
None of these
Belts are available in sets
Only one belt cannot be fitted with other used belts
The new belt will carry more than its share and result in short life
New and old belts will cause vibrations
0.75/ (0.75 + √v)
3/ (3 + v)
4.5/ (4.5 + v)
6/ (6 + v)
Brittle
Ductile
Elastic
Plastic
Actual size and the corresponding basic size
Maximum limit and the basic size
Minimum limit and the basic size
None of the above
Combined loading
Fatigue
Thermal stresses
Shock loading
P1 - P2
P1 + P2
2 × (P1 + P2)
[2 × (P1 + P2)] + Pc Where Pc is centrifugal tension
Thread
Middle
Shank
Head
Directly proportional to the polar moment of inertia and to the distance of the point from the axis
Directly proportional to the applied torque and inversely proportional to the polar moment of inertia
Directly proportional to the applied torque and the polar moment of inertia
Inversely proportional to the applied torque and the polar moment of inertia
Less than
Equal to
More than
None of these
1/sinθ
1/cosθ
1/tanθ
sinθ cosθ
2WD3n/Gd⁴
4WD3n/Gd⁴
8WD3n/Gd⁴
16WD3n/Gd⁴
T₁ - T₂ + Tc
T₁ + T₂ + Tc
(T₁ - T₂ + Tc)/2
(T₁ + T₂ + Tc)/2
Diameter of bolt
0.75 × diameter of bolt
1.25 × diameter of bolt
1.5 × diameter of bolt
Heavy load
Loose belt
Driving pulley too small
All of the above
Mild steel
Aluminium
Brass
Cast iron
10°-20°
30°-40°
40°-60°
60°-80°
Self locking bolts
Designed for shock load
Used in aircraft application
Provided with hexagonal depression in head
σ [1 + (b/2a)]
σ [1 + (2a/b)]
σ [1 + (b/3a)]
σ [1 + (3a/b)]