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
Correct Answer :
C. Could be either same or opposite to velocity
Related Questions
A single degree of freedom system is given by, m × (d²x/dt²) + c × (dx/dt) + sx = F.cosω.t with usual notations. It represents
Free vibration with damping
Free vibration without damping
Forced vibration with damping
Forced vibration without damping
Klein's construction can be used when
Crank has a uniform angular velocity
Crank has non-uniform velocity
Crank has uniform angular acceleration
Crank has uniform angular velocity and angular acceleration
The acceleration of a particle moving with simple harmonic motion, at any instant is given by
ωx
ω²x
ω²/x
ω³/x
Minimum number of teeth for involute rack and pinion arrangement for pressure angle of 20° is
18
20
30
34
A kinematic chain requires at least
2 links and 3 turning pairs
3 links and 4 turning pairs
4 links and 4 turning pairs
5 links and 4 turning pairs
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
The cam follower generally used in automobile engines is
Knife edge follower
Flat faced follower
Spherical faced follower
Roller follower
Oldham's coupling is the
Second inversion of double slider crank chain
Third inversion of double slider crank chain
Second inversion of single slider crank chain
Third inversion of slider crank chain
In railway axle boxes, the bearing used is
Deep groove ball bearing
Double row self aligning ball bearing
Double row spherical roller bearing
Cylindrical roller bearing
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
The swaying couple is due to the
Primary unbalanced force
Secondary unbalanced force
Two cylinders of locomotive
Partial balancing
What is the number of instantaneous centres for an eight link mechanism?
15
28
30
8
The acceleration of the particle moving with simple harmonic motion is _________ at the mean position.
Zero
Minimum
Maximum
None of these
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
In a simple train of wheels, the velocity ratio __________ the intermediate wheels.
Depends upon
Is independent of
Either A or B
None of these
For low and moderate speed engines, the cam follower should move with
Uniform velocity
Simple harmonic motion
Uniform acceleration and retardation
Cycloidal motion
When the load on the engine increases, it becomes necessary to increase the supply of working fluid and when the load decreases, less working fluid is required. The supply of the working fluid to the engine is controlled by a
D-slide valve
Governor
Meyer's expansion valve
Flywheel
A cam with a roller follower would constitute following type of pair
Lower pair
Higher pair
Open pair
Close pair
The engine of an aeroplane rotates in clockwise direction when seen from the tail end and the aeroplane takes a turn to the left. The effect of gyroscopic couple on the aeroplane will be
To dip the nose and tail
To raise the nose and tail
To raise the nose and dip the tail
To dip the nose and raise the tail
The acceleration of the reciprocating roller follower when it has contact with the straight flanks of the tangent cam, is given by
ω². (r₁ r₂). (1 - cos² θ)
ω². (r₁ + r₂). (1 + cos² θ)
ω². (r₁ + r₂). [(2 - cos² θ)/cos³ θ]
ω². (r₁ - r₂). (1 - sin² θ)
Transmission angle is the angle between
Input link and coupler
Input link and fixed link
Output link and coupler
Output link and fixed link
In an open pair, the two elements of a pair
Have a surface contact when in motion
Have a line or point contact when in motion
Are kept in contact by the action of external forces, when in motion
Are not held together mechanically
Which of the following statement is correct?
The primary unbalanced force is less than the secondary unbalanced force.
The primary unbalanced force is maximum twice in one revolution of the crank.
The unbalanced force due to reciprocating masses varies in magnitude and direction both.
The magnitude of swaying couple in locomotives is inversely proportional to the distance between the two cylinder centre lines
Efficiency of a screw jack is given by
tan (α + φ)/tanα
tanα/tan (α +φ)
tan (α - φ)/tanα
tanα/tan (α - φ)
When the particles of a body moves perpendicular to its axis, then the body is said to have
Longitudinal vibration
Transverse vibration
Torsional vibration
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
Which of the following property of the instantaneous centre is correct?
A rigid link rotates instantaneously relative to another link at the instantaneous centre for the configuration of the mechanism considered.
The two rigid links have no linear velocity relative to each other at the instantaneous centre.
The velocity of the instantaneous centre relative to any third rigid link is same whether the instantaneous centre is regarded as a point on the first rigid link or on the second rigid link.
All of the above
The primary unbalanced force is maximum _________ in one revolution of the crank.
Twice
Four times
Eight times
Sixteen times
When the addenda on pinion and wheel is such that the path of approach and path of recess are half of their maximum possible values, then the length of the path of contact is given by (where r = Pitch circle radius of pinion, R = Pitch circle radius of wheel, and φ = Pressure angle)
[(r² + R²) cosφ]/2
[(r² + R²) sinφ]/2
[(r + R) cosφ]/2
[(r + R) sinφ]/2
A simple spring-mass vibrating system has a natural frequency of fn. If the spring stiffness is halved and the mass is doubled, then the natural frequency will become
fn/2
2 fn
4 fn
8 fn