The value of Lewis form factor used in design of gears is
Dependent on number of teeth of a gear
Dependent on system of teeth
Independent of size of teeth
All of these
Correct Answer :
D. All of these
Related Questions
The building up of worn and undersized parts, subjected to repeated loads by electroplating is
Best method
Extremely hazardous
Has no effect as regards fatigue strength
Cheapest method
If the size of a standard specimen for a fatigue testing machine is increased, the endurance limit for the material will
Have same value as that of standard specimen
Increase
Decrease
None of these
When the shaft rotates in anticlockwise direction at slow speed in a bearing, it will
Have contact at the bottom most of the bearing
Move towards right of the bearing making no metal to metal contact
Move towards right of the bearing making the metal to metal contact
Move towards left of the bearing making metal to metal contact
The relation between the pitch of the chain (p) and pitch circle diameter of the sprocket (D) is given by (where T = Number of teeth on the sprocket)
p = D sin (90°/T)
p = D sin (120°/T)
p = D sin (180°/T)
p = D sin (360°/T)
According to Indian standard specifications, a grey cast iron designated by 'FG 200' means that the
Carbon content is 2%
Maximum compressive strength is 200 N/mm²
Minimum tensile strength is 200 N/mm²
Maximum shear strength is 200 N/mm²
A hot short metal is
Brittle when cold
Brittle when hot
Brittle under all conditions
Ductile at high temperature
The objective of crowning of the flat pulleys of belt drive is to
Prevent the belt from running off the pulley
Increase the power transmission capacity
Increase the belt velocity
Prevent the belt joint from damaging the belt surface
The included angle for the V-belt is usually
10°-20°
30°-40°
40°-60°
60°-80°
In an oil lubricated journal bearing, the coefficient of friction between the journal and the bearing
Remains constant at all speeds
Is minimum at zero speed and increases monotonically with increase in speed
Is maximum at zero speed and decreases monotonically with increase in speed
Becomes minimum at an optimum speed and then increases with further increase in speed
In order to ensure self locking in a screw jack, it is essential that helix angle is __________ friction angle.
Larger than
Smaller than
Equal to
None of these
According to Indian standard specifications, 100 H6/g5 means that the
Basic size is 100 mm
Actual size is 100 mm
Difference between the actual size and basic size is 100 mm
None of the above
The notch angle of the Izod impact test specimen is
10°
20°
30°
45°
The material generally used for aircraft components is
Mild steel
High speed steel
Stainless steel
Aluminium
In order to obtain bolt of uniform strength
Increase shank diameter
Increase its length
Drill an axial hole through head up to threaded portion so that shank area is equal to root area of thread
Tighten die bolt properly
For maximum power, the velocity of the belt will be
√(T/m)
√(T/2m)
√(T/3m)
None of these
The size of a cam depends upon
Base circle
Pitch circle
Prime circle
Pitch curve
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
The centre distance between two meshing involute gears is equal to
(Sum of base circle radii)/cosφ
(Difference of base circle radii)/cosφ
(Sum of pitch circle radii)/cosφ
(Difference of pitch circle radii)/cosφ
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 radial distance of a tooth from the pitch circle to the top of the tooth is called
Addendum
Dedendum
Clearance
Working depth
A leaf spring in automobiles is used
To apply forces
To measure forces
To absorb shocks
To store strain energy
When carbon in the cast iron is principally in the form of graphite, the cast iron will be of
Brown colour
Yellow colour
White colour
Grey colour
A backing ring is used inside the pipe joint when making a
Butt weld
Fillet weld
Sleeve weld
Socket weld
According to I.B.R., the efficiency of a double riveted butt joint with double cover straps of equal width should be
45 to 60 %
63 to 70 %
70 to 83 %
80 to 90 %
The power transmitted by the belt drive can be increased by
Increasing the initial tension in the belt
Dressing the belt to increase the coefficient of friction
Increasing wrap angle by using idler pulley
All of the above methods
The included angle for the British Association thread is
29°
55°
47.3°
60°
When screw threads are to be used in a situation where power is being transmitted in one direction only, then the screw threads suitable for this will be
Knuckle threads
Square threads
Acme threads
Buttress threads
The lower deviation is the algebraic difference between the
Actual size and the corresponding basic size
Maximum limit and the basic size
Minimum limit and the basic size
None of the above
If T₁ and T₂ are the tensions on the tight and slack sides of the belt respectively, and Tc is the centrifugal tension, then initial tension in the belt is equal to
T₁ - T₂ + Tc
T₁ + T₂ + Tc
(T₁ - T₂ + Tc)/2
(T₁ + T₂ + Tc)/2
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