The inversion of a mechanism is
Changing of a higher pair to a lower pair
Turning its upside down
Obtained by fixing different links in a kinematic chain
Obtained by reversing the input and output motion
Correct Answer :
C. Obtained by fixing different links in a kinematic chain
Related Questions
When there is a reduction in amplitude over every cycle of vibration, then the body is said to have
Free vibration
Forced vibration
Damped vibration
Under damped vibration
The equation of motion for a vibrating system with viscous damping is (d²x/dt²) + (c/m). (dx/dt) + (s/m). x = 0 If the roots of this equation are real, then the system will be
Over-damped
Under damped
Critically damped
Without vibrations
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 four stroke I.C. engine, the turning moment during the compression stroke is
Positive throughout
Negative throughout
Positive during major portion of the stroke
Negative during major portion of the stroke
When a body moves with simple harmonic motion, the product of its periodic time and frequency is equal to
Zero
One
π/2
π
A higher pair has__________.
Point contact
Surface contact
No contact
None of the above
The flank of the tooth is the surface of the tooth __________ the pitch surface.
Above
Below
At
None of these
The motion between a pair when limited to a definite direction, irrespective of the direction of force applied, is known as
Completely constrained motion
Incompletely constrained motion
Successfully constrained motion
None of these
Which gear is used for connecting two coplanar and intersecting shafts?
Spur gear
Helical gear
Bevel gear
None of the above
Sense of tangential acceleration of a link
Is same as that of velocity
Is opposite to that of velocity
Could be either same or opposite to velocity
Is perpendicular to that of velocity
The equivalent length of a simple pendulum which gives the same frequency as a compound pendulum is
h/(kG² + h²)
(kG² + h²)/h
h²/(kG² + h²)
(kG² + h²)/h²
In a hydrodynamic journal bearing, there is
A very thin film of lubricant between the journal and the bearing such that there is contact between the journal and the bearing
A thick film of lubricant between the journal and the bearing
No lubricant between the journal and the bearing
A forced lubricant between the journal and the bearing
Peaucelliers mechanism has
Eight links
Six links
Four links
Twelve links
The frictional torque transmitted by a cone clutch is same as that of
Flat pivot bearing
Flat collar bearing
Conical pivot bearing
Truncated conical pivot bearing
Which of the following mechanism is obtained from lower pair?
Gyroscope
Pantograph
Valve and valve gears
All of the above
In order to facilitate starting of locomotive in any position, the cranks of a locomotive with two cylinders, are placed at
45° to each other
90° to each other
120° to each other
180° to each other
For an isochronous Hartnell governor (where r₁ and r₂ = Maximum and minimum radius of rotation of balls respectively, S₁ and S₂ = Maximum and minimum force exerted on the sleeve respectively, and M = Mass on the sleeve)
(m.g + S₁)/(m.g + S₂) = r₁/r₂
(m.g - S₁)/(m.g - S₂) = r₂/r₁
S₁/S₂ = r₁/r₂
S₂/S₁ = r₁/r₂
The coriolis component of acceleration exists whenever a point moves along a path that has
Linear displacement
Rotational motion
Gravitational acceleration
Tangential acceleration
The effort of a Porter governor is equal to (where c = Percentage increase in speed, m = Mass of ball, and M = Mass on the sleeve)
c (m - M) g
c (m + M) g
c/(m + M) g
c/(m - M) g
A spring controlled governor is found unstable. It can be made stable by
Increasing the spring stiffness
Decreasing the spring stiffness
Increasing the ball mass
Decreasing the ball mass
The ratio of maximum fluctuation of energy to the workdone per cycle is called
Fluctuation of energy
Maximum fluctuation of energy
Coefficient of fluctuation of energy
None of these
The main disadvantage of the sliding pair is that it is
Bulky
Wears rapidly
Difficult to manufacture
Both (A) and (B) above
To obviate axial thrust, following gear drive is used
Double helical gears having opposite teeth
Double helical gears having identical teeth
Single helical gear in which one of the teeth of helix angle a is more
Mutter gears
In a radial cam, the follower moves
In a direction perpendicular to the cam axis
In a direction parallel to the cam axis
In any direction irrespective of the cam axis
Along the cam axis
If two moving elements have surface contact in motion, such pair is known as
Sliding pair
Rolling pair
Surface pair
Higher pair
The direction of Coriolis component of acceleration is the direction
Of relative velocity vector for the two coincident points rotated by 90° in the direction of the angular velocity of the rotation of the link
Along the centripetal acceleration
Along tangential acceleration
Along perpendicular to angular velocity
A governor is said to be stable, if the
Radius of rotation of balls increases as the equilibrium speed decreases
Radius of rotation of balls decreases as the equilibrium speed decreases
Radius of rotation of balls increases as the equilibrium speed increases
Radius of rotation of balls decreases as the equilibrium speed increases
Creep in belt drive is due to
Weak material of the belt
Weak material of the pulley
Uneven extensions and contractions of the belt when it passes from tight side to slack side
Expansion of the belt
With usual notations for different parameters involved, the maximum fluctuations of energy for a flywheel is given by
2ECS
ECS/2
2ECS²
2E²CS
The magnitude of linear velocity of a point B on a link AB relative to point A is (Where ω = Angular velocity of the link AB)
ω × AB
ω × (AB)²
ω² × AB
(ω × AB)²