In a mechanism, the fixed instantaneous centres are those centres which
Remain in the same place for all configurations of the mechanism
Vary with the configuration of the mechanism
Moves as the mechanism moves, but joints are of permanent nature
None of the above
Correct Answer :
A. Remain in the same place for all configurations of the mechanism
Related Questions
The danger of breakage and vibration is maximum
Below the critical speed
Near the critical speed
Above the critical speed
None of these
Lower 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
Whitworth quick return mechanism is obtained by inversion of
Slider crank mechanism
Kinematic chain
Five link mechanism
Roller cam mechanism
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
The type of pair formed by two elements which are so connected that one is constrained to turn or revolve about a fixed axis of another element is known as
Turning pair
Rolling pair
Sliding pair
Spherical pair
The ratio of maximum fluctuation of speed to the mean speed is called
Fluctuation of speed
Maximum fluctuation of speed
Coefficient of fluctuation of speed
None of these
Effort of a governor is the
Mean force exerted at the sleeve for a given percentage change of speed
Workdone at the sleeve for maximum equilibrium speed
Mean force exerted at the sleeve for maximum equilibrium speed
None of the above
To transmit power from one rotating shaft to another whose axes are neither parallel nor intersecting, use?
Spur gear
Spiral gear
Bevel gear
Worm gear
A foot step bearing and rotor of a vertical turbine form examples of
Incompletely constrained motion
Partially constrained motion
Completely constrained motion
Successfully constrained motion
In a differential band brake as shown in the below figure, if the length OB is greater than OA, then the force P at C should act in the downward direction. 
Yes
No
Unpredictable
None of these
A typewriter mechanism has 7 numbers of binary joints, six links and none of higher pairs. The mechanism is
Kinematically sound
Not sound
Soundness would depend upon which link is kept fixed
Data is not sufficient to determine same
In elliptical trammels
All four pairs are turning
Three pairs turning and one pair sliding
Two pairs turning and two pairs sliding
One pair turning and three pairs sliding
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
When the pitching of a ship is __________ the effect of gyroscopic couple acting on it will be to move the ship towards port side.
Upward
Downward
Forward
Backward
When a rigid body is suspended vertically and it oscillates with a small amplitude under the action of the force of gravity, the body is known as
Simple pendulum
Compound pendulum
Torsional pendulum
Second's pendulum
Frequency of vibrations is usually expressed in
Number of cycles per hour
Number of cycles per minute
Number of cycles per second
None of these
If the rotating mass of a rim type flywheel is distributed on another rim type flywheel whose mean radius is half the mean radius of the former, then energy stored in the latter at the same speed will be
Four times the first one
Same as the first one
One fourth of the first one
One and a half times the first one
A friction circle is a circle drawn when a journal rotates in a bearing. Its radius depends upon the coefficient of friction and the
Magnitude of the forces on journal
Angular velocity of journal
Clearance between journal and bearing
Radius of journal
The included angle for the V-belt is usually
10° to 20°
20° to 30°
30° to 40°
60° to 80°
The essential condition of placing the two masses, so that the system becomes dynamically equivalent, is (where l₁ and l₂ = Distance of two masses from the centre of gravity of the body, and kG = Radius of gyration of the body)
l₁ = kG
l₂ = kG
l₁l₂ = kG
l₁l₂ = kG²
The example of higher pair is
Belt, rope and chain drives
Gears, cams
Ball and roller bearings
All of the above
The flank of the tooth is the surface of the tooth __________ the pitch surface.
Above
Below
At
None of these
Ackermann steering gear consists of
Sliding pairs
Turning pairs
Rolling pairs
Higher pairs
The acceleration of a particle at any instant has two components i.e. radial component and tangential component. These two components will be
Parallel to each other
Perpendicular to each other
Inclined at 45°
Opposite to each other
The lower pair is a
Open pair
Closed pair
Sliding pair
Point contact pair
In a screw jack, the effort required to lift the load W is given by (where α = Helix angle, and φ = Angle of friction)
P = W tan(α - φ)
P = W tan(α + φ)
P = W tan(φ - α)
P = W cos(α + φ)
The transmissibility, for all values of damping factor, will be less than unity, if ω/ωn is
Equal to 1
Less than 2
Equal to 2
Greater than 2
The Klein's diagram is used when
Crank has uniform angular velocity
Crank has nonuniform angular velocity
Crank has uniform angular acceleration
Crank has nonuniform angular acceleration
3.The retardation of a flat faced follower when it has contact at the apex of the nose of a circular arc cam, is given by (where OQ = Distance between the centre of circular flank and centre of nose)
ω² × OQ
ω² × OQ sinθ
ω² × OQ cosθ
ω² × OQ tanθ
In a mechanism, the fixed instantaneous centres are those centres which
Remain in the same place for all configurations of the mechanism
Vary with the configuration of the mechanism
Moves as the mechanism moves, but joints are of permanent nature
None of the above