The frictional torque transmitted in a conical pivot bearing, considering uniform pressure, is (where R = Radius of shaft, and α = Semi-angle of the cone)
(1/2) μ W R cosecα
(2/3) μ W R cosecα
(3/4) μ W R cosecα
μ W R cosecα
Correct Answer :
B. (2/3) μ W R cosecα
Related Questions
In gears, interference takes place when
The tip of a tooth of a mating gear digs into the portion between base and root circles
Gears do not move smoothly in the absence of lubrication
Pitch of the gears is not same
Gear teeth are undercut
Kinematic pairs are those which have
Point or line contact between the two elements when in motion
Surface contact between the two elements when in motion
Elements of pairs not held together mechanically
Two elements that permit relative motion
A spring controlled governor is said to be isochronous when the controlling force
Increases as the radius of rotation decreases
Increases as the radius of rotation increases
Decreases as the radius of rotation increases
Remain constant for all radii of rotation
Coriolis component is encountered in
Quick return mechanism of shaper
Four bar chain mechanism
Slider crank mechanism
Both (A) and (C) above
A pantograph is a mechanism with
Lower pairs
Higher pairs
Rolling pairs
Turning pairs
When the crank is at the outer dead centre, in a reciprocating steam engine, then the acceleration of the piston will be
ω² r {(n + 1)/n}
ω² r {(n - 1)/n}
ω² r {n/(n + 1)}
ω² r {n/(n - 1)}
When the belt is stationary, it is subjected to some tension known as initial tension. The value of this tension is equal to the
Tension in the tight side of the belt
Tension in the slack side of the belt
Sum of the tensions on the tight side and slack side of the belt
Average tension of the tight side and slack side of the belt
The coefficient of fluctuation of speed is __________ of maximum fluctuation of speed and the mean speed.
Sum
Difference
Product
Ratio
The periodic time of a compound pendulum is __________ when the distance between the point of suspension and the centre of gravity is equal to the radius of gyration of the body about its centre of gravity.
Zero
Minimum
Maximum
None of these
When a body moves with simple harmonic motion, the product of its periodic time and frequency is equal to
Zero
One
π/2
π
The two links OA and OB are connected by a pin joint at O. If the link OA turns with angular velocity ω₁ rad/s in the clockwise direction and the link OB turns with angular velocity ω₂ rad/s in the anticlockwise direction, then the rubbing velocity at the pin joint O is (where r = Radius of the pin at O)
ω₁.ω₂.r
(ω₁ - ω₂) r
(ω₁ + ω₂) r
(ω₁ - ω₂) 2r
A reed type tachometer use the principle of
Longitudinal vibration
Torsional vibration
Transverse vibration
Damped free vibration
In a cone pulley, if the sum of radii of the pulleys on the driving and driven shafts is Constant, then
Open belt drive is recommended
Crossed belt drive is recommended
Both open belt drive and crossed belt drive is recommended
The drive is recommended depending upon the torque transmitted
The lower pair is a
Open pair
Closed pair
Sliding pair
Point contact pair
The motion of a shaft in a circular hole is an example of
Completely constrained motion
Incompletely constrained motion
Successfully constrained motion
None of these
A rotor which is balanced statically but not dynamically is supported on two bearings L apart and at high speed of the rotor, reaction on the left bearing is R. The right side of the bearing is shifted to a new position 2L apart from the left bearing. At the same rotor speed, dynamic reaction on the left bearing in the new arrangement will
Remain same as before
Become equal to 2R
Become equal to R/2
Become equal to R/4
For the brake to be self locking, the force P at C shown in the below figure, should 
Be zero
Act in upward direction
Act in downward direction
None of these
It is required to connect two parallel shafts, the distance between whose axes is small and variable. The shafts are coupled by
Universal joint
Knuckle joint
Oldham's coupling
Flexible coupling
The secondary unbalanced force is maximum when the angle of inclination of the crank with the line of stroke is
0° and 90°
180° and 360°
Both (A) and (B)
None of these
Open pairs are those which have
Point or line contact between the two elements when in motion
Surface contact between the two elements when in motion
Elements of pairs not held together mechanically
Two elements that permit relative motion
Which of the following statement is correct?
The power absorbed in operating the piston valve is less than D-slide valve
The wear of the piston valve is less than the wear of the D-slide valve
The D-slide valve is also called outside admission valve.
All of the above
The dedendum circle diameter is equal to (where, φ = Pressure angle)
Pitch circle dia. × cosφ
Addendum circle dia. × cosφ
Clearance circle dia. × cosφ
Pitch circle dia. × sinφ
The power transmitted by a belt is maximum when the maximum tension in the belt is _________ of centrifugal tension.
One-third
Two-third
Double
Three times
Which of the following is an open pair?
Journal bearing
Ball and Socket joint
Leave screw and nut
None of the above
For an involute gear, the ratio of base circle radius and pitch circle radius is equal to
sinφ
cosφ
secφ
cosecφ
In the below figure, PC is the connecting rod and OC is the crank making an angle θ with the line of stroke PO and rotates with uniform angular velocity at ω rad/s. The Klien's acceleration diagram for determining the acceleration of the piston P is shown by quadrilateral CQNO. The acceleration of the piston P with respect to the crankpin C is given by 
ω² × NO
ω² × CO
ω² × CN
ω² × QN
If two moving elements have surface contact in motion, such pair is known as
Sliding pair
Rolling pair
Surface pair
Higher pair
For fluctuating loads, well suited bearing is
Ball bearing
Roller bearing
Needle roller bearing
Thrust bearing
In order to give the primary balance of the reciprocating parts of a multi-cylinder inline engines,
The algebraic sum of the primary forces must be equal to zero
The algebraic sum of the couples about any point in the plane of the primary forces must be equal to zero
Both (A) and (B)
None of these
When the pitching of a ship is upward, the effect of gyroscopic couple acting on it will be
To move the ship towards starboard
To move the ship towards port side
To raise the bow and lower the stern
To raise the stern and lower the bow