Q.1

The equation of motion for a single degree of freedom system with viscous damping is . The damping ratio of the system is

  • 9/8
  • 9/82
  • 9/16
  • 9/128
Q.2
The unbalanced primary forces in a reciprocating engine are
  • Balanced by secondary forces
  • Balanced completely
  • Balanced partially
  • Not balanced
Q.3
The partial balancing of reciprocating parts in locomotives produces
  • hammer blow
  • swaying couple
  • variation in tractive force along the line of stroke
  • all of the above
Q.4
Crowning on pulleys helps
  • In increasing velocity ratio
  • In decreasing the slip of the belt
  • For automatic adjustment of belt position so that belt runs centrally
  • Increase belt and pulley life
Q.5
The equation of motion for a single degree of freedom system with viscous damping is 4(dx²/dt²) + 9(dx/dt) + 16x. The damping ratio of the system is
  • 9/8
  • 9/82
  • 9/16
  • 9/128
Q.6
The critical speed of a shaft with a disc supported in between is equal to the natural frequency of the system in
  • Transverse vibrations
  • Torsional vibrations
  • Longitudinal vibrations
  • All of these
Q.7
Which of the following is an example of sliding pair?
  • Piston and cylinder of a reciprocating steam engine
  • Shaft with collars at both ends fitted into a circular hole
  • Lead screw of a lathe with nut
  • Ball and a socket joint
Q.8
The example of lower pair is
  • Shaft revolving in a bearing
  • Straight line motion mechanisms
  • Automobile steering gear
  • All of the above
Q.9
The Kutzbach criterion for determining the number of degrees of freedom (n) is (where l = number of links, j = number of joints and h = number of higher pairs)
  • n = 3(l - 1) - 2j - h
  • n = 2(l - 1) - 2j - h
  • n = 3(l - 1) - 3j - h
  • n = 2(l - 1) - 3j - h
Q.10
The maximum fluctuation of energy is the
  • Difference between the maximum and minimum energies
  • Sum of the maximum and minimum energies
  • Variations of energy above and below the mean resisting torque line
  • Ratio of the mean resisting torque to the work-done per cycle
Q.11
A disturbing mass m₁ attached to the rotating shaft may be balanced by a single mass m₂ attached in the same plane of rotation as that of m₁, such that (where r₁ and r₂ are the radii of rotation of m₁ and m₂ respectively)
  • m₁ r₂ = m₂ r₁
  • m₁ r₁ = m₂ r₂
  • m₁ m₂ = r₁ r₂
  • None of these
Q.12
A chain comprises of 5 links having 5 joints. Is it kinematic chain?
  • Yes
  • No
  • It is a marginal case
  • Data are insufficient to determine it
Q.13
Efficiency of a screw jack is given by
  • tan (α + φ)/tanα
  • tanα/tan (α +φ)
  • tan (α - φ)/tanα
  • tanα/tan (α - φ)
Q.14
A Hartnell governor has its controlling force (Fc) given by Fc = ar + b, where r is the radius of rotation and a and b are constants. The governor becomes isochronous when
  • a is +ve and b = 0
  • a = 0 and b is +ve
  • a is +ve and b is -ve
  • a is +ve and b is also +ve
Q.15
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
Q.16
In a kinematic chain, a quaternary joint is equivalent to
  • One binary joint
  • Two binary joints
  • Three binary joints
  • Four binary joints
Q.17
Which of the following is an open pair?
  • Ball and socket joint
  • Journal bearing
  • Lead screw and nut
  • Cam and follower
Q.18
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
Q.19
A universal joint is an example of
  • Higher pair
  • Lower pair
  • Rolling pair
  • Sliding pair
Q.20
A mass of 1 kg is attached to the end of a spring with a stiffness of 0.7 N/mm. The critical damping coefficient of this system is
  • 1.4 N-s/m
  • 18.52 N-s/m
  • 52.92 N-s/m
  • 529.2 N-s/m
Q.21
The gear train usually employed in clocks is a
  • simple gear train
  • reverted gear train
  • sun and planet gear
  • differential gear
Q.22
In order to give the primary balance of the reciprocating parts of a multi-cylinder in-line 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
Q.23
The frictional torque transmitted in a multi-collared shaft is same as that of a single collared shaft.
  • Right
  • Wrong
Q.24
A circular bar moving in a round hole is an example of
  • Incompletely constrained motion
  • Partially constrained motion
  • Completely constrained motion
  • Successfully constrained motion
Q.25
The D-slide valve is also known as
  • Inside admission valve
  • Outside admission valve
  • Piston slide valve
  • None of these
Q.26
Which of the following is a lower pair?
  • Ball and socket i
  • Piston and cylinder
  • Cam and follower
  • Both (A) and (B) above
Q.27
Critical damping is a function of
  • Mass and stiffness
  • Mass and damping coefficient
  • Mass and natural frequency
  • Damping coefficient and natural frequency
Q.28
The Coriolis component of acceleration is taken into account for
  • Slider crank mechanism
  • Four bar chain mechanism
  • Quick return motion mechanism
  • All of these
Q.29
An automobile steering gear is an example of
  • sliding pair
  • rolling pair
  • lower pair
  • higher pair
Q.30
In order to balance the reciprocating masses,
  • primary forces and couples must be balanced
  • secondary forces and couples must be balanced
  • both (a) and (b)
  • none of these
Q.31
In a screw jack, the effort required to lower the load W is given by
  • P = W tan(α - φ)
  • P = W tan(α + φ)
  • P = W tan(φ - α)
  • P = W cos(α + φ)
Q.32
A pair of friction discs is an example of rolling pair.
  • True
  • False
Q.33
The pressure angle of a cam is the angle between the direction of the follower motion and a normal to the
  • pitch circle
  • base circle
  • pitch curve
  • prime circle
Q.34
If the pressure angle is __________, a reciprocating follower will jam in its bearings.
  • Small
  • Too small
  • Large
  • Too large
Q.35
Governor is used in automobile to
  • Decrease the variation of speed
  • Maximize the fuel economy
  • Limit the vehicle speed
  • Maintain constant engine speed
Q.36
In a Hartnell governor, if a spring of greater stiffness is used, then the governor will be
  • Less sensitive
  • More sensitive
  • Unaffected of sensitivity
  • Isochronous
Q.37
The axis of precession is __________ to the plane in which the axis of spin is going to rotate.
  • Parallel
  • Perpendicular
  • Both A and B
  • None of these
Q.38
The swaying couple is maximum or minimum when the angle of inclination of the crank to the line of stroke (θ) is equal to
  • 90° and 180°
  • 45° and 225°
  • 180° and 270°
  • 270° and 360°
Q.39
A shaft has an attached disc at the centre of its length. The disc has its centre of gravity located at a distance of 2 mm from the axis of the shaft. When the shaft is allowed to vibrate in its natural bow-shaped mode, it has a frequency of vibration ofrad/s. When the shaft is rotated atr.p.m., it will whirl with a radius of
  • 2 mm
  • 2.22 mm
  • 2.50 mm
  • 3.0 mm
Q.40
The static friction
  • bears a constant ratio to the normal reaction between the two surfaces
  • is independent of the area of contact, between the two surfaces
  • always acts in a direction, opposite to that in which the body tends to move
  • all of the above
Q.41
When a particle moves round the circumference of a circle of radius r with ω rad/s, then its maximum acceleration is ω2r.
  • Right
  • Wrong
Q.42
The sliding pairs, turning pairs and screw pairs form lower pairs.
  • True
  • False
Q.43
Davis steering gear consists of
  • Sliding pairs
  • Turning pairs
  • Rolling pairs
  • Higher pairs
Q.44
Ackermann steering gear consists of
  • Sliding pairs
  • Turning pairs
  • Rolling pairs
  • Higher pairs
Q.45
Which of the following mechanism is obtained from lower pair?
  • Gyroscope
  • Pantograph
  • Valve and valve gears
  • All of the above
Q.46
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
Q.47
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
Q.48
The rotor of a ship rotates in clockwise direction when viewed from stern and the ship takes a right turn. The effect of gyroscopic couple acting on it will be to raise the stern and lower the bow.
  • Agree
  • Disagree
Q.49
Whitworth quick return motion mechanism consists of three turning pairs and one sliding pair.
  • Right
  • Wrong
Q.50
The gears are termed as medium velocity gears, if their peripheral velocity is
  • 1 - 3 m/s
  • 3 - 15 m/s
  • 15 - 30 m/s
  • 30 - 50 m/s
0 h : 0 m : 1 s