In higher pair, the relative motion is
Purely turning
Purely sliding
Purely rotary
Combination of sliding and turning
Correct Answer :
D. Combination of sliding and turning
Related Questions
A machine mounted on a single coil spring has a period of free vibration of tp . If the spring is cut into four equal parts and placed in parallel and the machine is mounted on them, then the period of free vibration of the new system will become
tp /16
tp /4
4 tp
16 tp
The method of direct and reverse cranks is used in engines for
The control of speed fluctuations
Balancing of forces and couples
Kinematic analysis
Vibration analysis
Which type of gear train is used in clock mechanism to join hour hand and minute hand?
Simple gear train
Compound gear train
Reverted gear train
Epicyclic gear train
A shaft carrying two rotors at its ends will have
No node
One node
Two nodes
Three nodes
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
If the radius of gyration of a compound pendulum about an axis through e.g. is more, then its frequency of oscillation will be
Less
More
Same
Data are insufficient to determine same
When the nature of contact between the elements of a pair is such that it can only slide relative to the other, the pair is known as a
Screw pair
Spherical pair
Turning pair
Sliding pair
The Coriolis component of acceleration acts
Along the sliding surface
Perpendicular to the sliding surface
At 45° to the sliding surface
Parallel to the sliding surface
The secondary unbalanced force is __________ the primary unbalanced force.
One-half
Two-third
n times
1/n times
The contact ratio is the ratio of
Length of pair of contact to the circular pitch
Length of arc of contact to the circular pitch
Length of arc of approach to the circular pitch
Length of arc of recess to the circular pitch
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 example of successfully constrained motion is a
Motion of an I.C. engine valve
Motion of the shaft between a footstep bearing
Piston reciprocating inside an engine cylinder
All of the above
The distance by which the __________ of the D-slide valve overlaps the steam port is called exhaust lap.
Inner edge
Outer edge
Corners
None of these
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
The Scott-Russell mechanism consists of
Sliding and turning pairs
Sliding and rotary pairs
Turning and rotary pairs
Sliding pairs only
Which of the following is a higher pair?
Turning pair
Screw pair
Belt and pulley
None of the above
In a steam engine, one method of obtaining the earlier cut-off with a simple slide valve is by increasing the angle of advance of the eccentric while the throw of the eccentric, steam lap and exhaust lap are kept constant. This method will
Cause withdrawing or throttling of steam
Reduce length of effective stroke of piston
Reduce maximum opening of port to steam
All of these
The critical speed of a shaft depends upon its
Mass
Stiffness
Mass and stiffness
Stiffness and eccentricity
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
Idler pulley is used
For changing the direction of motion of the belt
For applying tension
For increasing velocity ratio
All of the above
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
A shaft carrying three rotors will have
No node
One node
Two nodes
Three nodes
In a gear having involute teeth, the normal to the involute is a tangent to the
Pitch circle
Base circle
Addendum circle
Dedendum circle
Cam size depends upon
Base circle
Pitch circle
Prime circle
Outer circle
The contact ratio for gears is
Zero
Less than one
Greater than one
Infinity
The example of lower pair is
Shaft revolving in a bearing
Straight line motion mechanisms
Automobile steering gear
All of the above
The radial distance of a tooth from the pitch circle to the bottom of the tooth is called
Dedendum
Addendum
Clearance
Working depth
What is the number of instantaneous centres for an eight link mechanism?
15
28
30
8
V-belts are usually used for
Long drives
Short drives
Long and short drives
None of these
If the pressure angle is __________, a reciprocating follower will jam in its bearings.
Small
Too small
Large
Too large