300+ REAL TIME Machine Kinematics Objective Questions & Answers 2023

250+ TOP MCQs on Pulleys and Answers

Machine Kinematics Multiple Choice Questions on “Pulleys”.

1. In a wheel and differential axle, the diameter of the effort wheel is 400 mm. The radii of the load axles are 150mm and 100 mm respectively. The diameter of the rope is 10 mm. Find the load which can be lifted by an effort of 100 N, assuming an efficiency of the machine to be 75%.
a) 800 N
b) 725 N
c) 615 N
d) none of the mentioned

Answer: c
Clarification: Diameter of effort wheel, D = 400 mm
Diameter of longer axle, d₁ = 2 x 150 = 300 mm
Diameter of the smaller axle, d₂ = 2 x 100 = 200 mm
Diameter of the rope, d_r = 10 mm

therefore, V.R. = 2(D + d_r )/(d₁ + d_r ) – (d₂ + d_r )
= 2(400 + 10)/ (300 + 10) – (200 + 10)
= 820/100 = 8.2
Effort, P = 100 N
ȵ = 75%
Let W = load which can be lifted by the machine

ȵ = M.A./V.R.
0.75 = W/P x 8.2
W = 0.75 x 100 x 8.2 = 615 N.

2. Four movable pulleys are arranged as in the first system. If the weight of each pulley is 5 N, calculate the effort which can lift a load of 10 kN.
a) 629.7 N
b) 615 N
c) 625 N
d) none of the mentioned

Answer: a
Clarification: We know that M.A. = 2ⁿW/W + w(2ⁿ – 1)
where W = load to be lifted
w = weight of each pulley
n = no. of movable pulleys

therefore, M.A. = 2⁴ x 10000/10000 + 5(2⁴ – 1) = 10000/P
P = 10000 + 5(2⁴ – 1)/ 2⁴ = 629.7 N.

3. A person weighing 600 N platform attached to the lower block of a system of 5 pulleys arranged in the second system. The platform and the lower block weigh 100N. The man himself supports by exerting a downward pull at the free end of the rope. Neglecting friction, the minimum pull of the man will be
a) 1000 N
b) 200 N
c) 116.7 N
d) none of the mentioned

Answer: c
Clarification: n = total number of pulleys in the system = 5
W = 600 N
Weight of the lower block and platform = 100 N
Total weight = 600 + 100 = 700 N
Let the pull exerted by the man be P newton.
Due to this pull the effective load on the lower platform will reduce to (700 – P)
nP = effective load = 700 – P
therefore, 5P = 700 -P
5P = 700
P = 116.7 N.

4. Five pulleys are arranged in the second system of pulleys. When not loaded the effort required to raise the movable block is 35N. Further wastage in friction increases the pull at the rate of 3% of the load lifted. What is the effort required to raise a load of 2kN?
a) 500 N
b) 400 N
c) 495 N
d) none of the mentioned

Answer: c
Clarification: n = no. of pulleys = 5
Frictional effort at zero loading = 35N
Frictional effort at 2 kN loading = 35 + 2000 x 3/100 = 95 N
When the system is considered frictionless nP = W
5P = 2000
P = 400 N
Hence total effort = 400 + 95 = 495 N.

5. Five pulleys are arranged in the second system of pulleys. When not loadwd the effort required to raise the movable block is 35N. Further wastage in friction increases the pull at the rate of 3% of the load lifted. What is the efficiency of the system at 2kN?
a) 80%
b) 80.81%
c) 80.50%
d) none of the mentioned

Answer: b
Clarification: n = no. of pulleys = 5
Frictional effort at zero loading = 35N
Frictional effort at 2 kN loading = 35 + 2000 x 3/100 = 95 N
When the system is considered frictionless nP = W
5P = 2000
P = 400 N
Hence total effort = 400 + 95 = 495 N
Efficiency at this load = effort without friction/effort with friction
= 400/495 x 100
= 80.81%.

6. In a weston differential pulley block, the number of recesses in the smaller wheel is 9/10 of that of the larger wheel. If the efficiency of the machine is 50%, find the load lifted by an effort of 300N.
a) 2000N
b) 3000N
c) 4000N
d) none of the mentioned

Answer: b
Clarification: Let the recesses in the larger wheel, n₁ = 10
Recesses in the smaller wheel, n₂ = 9/10 x 10 = 9

V.R. = 2n₁ /n₁ – n₂ = 2×10/10 – 9 = 20
and mechanical advantage M.A. = W/P
= W/300
efficiency = M.A./V.R.
0.5 = W/300×20
W = 3000N.

7. If the velocity ratio for an open belt drive is 8 and the speed of driving pulley is 800 r.p.m, then considering an elastic creep of 2% the speed of the driven pulley is
a) 104.04 r.p.m
b) 102.04 r.p.m
c) 100.04 r.p.m
d) 98.04 r.p.m

Answer: d
Clarification: Velocity Ratio = Velocity of belt on driver/Velocity of belt on driven
Velocity of belt on driven = 800/8 = 100 r.p.m
Elastic creep = velocity of belt at driven pulley – Velocity of driven pulley
0.02 × Vp = [100-Vp]
Vp = 100/1.02 = 98.04r.p.m.

8. If the angle of wrap on smaller pulley of diameter 250 mm is 120⁰ and diameter of larger pulley is twice the diameter of smaller pulley, then the centre distance between the pulleys for an open belt drive is
a) 1000 mm
b) 750 mm
c) 500 mm
d) 250 mm

Answer: d
Clarification: sin α = (D -d)/2c
Angle of wrap on smaller pulley = п – 2α
2п/3 = п – 2sin^-1(D -d)/2c
c = 250 mm.

9. In short open-belt drives, an idler pulley is used in order to decrease the angle of contact on the smaller pulley for higher power transmission.
a) True
b) False

Answer: b
Clarification: In short open-belt drives, an idler pulley is used in order to increase the angle of contact on the smaller pulley for higher power transmission.

10. In design of arms of a pulley, in belt drive, the cross-section of the arm is elliptical with minor axis placed along the plane of rotation.
a) True
b) False

Answer: b
Clarification: Arms of a pulley in belt drive are subjected to complete reversal of stresses and is designed for bending in the plane of rotation.

250+ TOP MCQs on Bevel Gears – 2 and Answers

Machine Kinematics Questions and Answers for Aptitude test on “Bevel Gears – 2”.

1. The mathematical form of the bevel tooth profile which closely resembles a spherical involute but is fundamentally different is
a) crown
b) back cone
c) octoid
d) none of the mentioned
Answer: c
Clarification: Octoid is the mathematical form of the bevel tooth profile which closely resembles a spherical involute but is fundamentally different is
The sharp corner orming the outside diameter is crown.

2. The angle formed between an element of the pitch cone and the bevel gear axis is
a) shaft angle
b) pitch angle
c) spiral angle
d) none of the mentioned
Answer: b
Clarification: The angle between the tooth trace and an element of the pitch cone, corresponding to helix angle in helical gears is spiral angle.
The angle formed between an element of the pitch cone and the bevel gear axis is pitch angle.

3. The angle between the tooth trace and an element of the pitch cone, corresponding to helix angle in helical gears is
a) shaft angle
b) pitch angle
c) spiral angle
d) none of the mentioned
Answer: c
Clarification: The angle between the tooth trace and an element of the pitch cone, corresponding to helix angle in helical gears is spiral angle.
The angle formed between an element of the pitch cone and the bevel gear axis is pitch angle.

4. The diameter and plane of rotation surface or shaft centre which is used for locating the gear blank during fabrication of the gear teeth is known as
a) crown
b) back cone
c) generating mounting surface
d) none of the mentioned
Answer: c
Clarification: The diameter and plane of rotation surface or shaft centre which is used for locating the gear blank during fabrication of the gear teeth is known as generating mounting surface.

5. The sharp corner orming the outside diameter is
a) crown
b) back cone
c) octoid
d) none of the mentioned
Answer: a
Clarification: The sharp corner orming the outside diameter is crown.
The length of teeth along the cone distance is face width.

6. The angle between elements of the face cone and pitch cone is
a) addendum angle
b) pitch angle
c) spiral angle
d) none of the mentioned
Answer: a
Clarification: The angle between mating bevel gear axes, also the sum of the two pitch angles is spiral angle.
The angle between elements of the face cone and pitch cone is addendum angle.

7. The angle between mating bevel gear axes, also the sum of the two pitch angles is
a) shaft angle
b) pitch angle
c) spiral angle
d) none of the mentioned
Answer: c
Clarification: The angle between mating bevel gear axes, also the sum of the two pitch angles is spiral angle.
The angle between elements of the face cone and pitch cone is addendum angle.

8. The length of teeth along the cone distance is
a) crown
b) face width
c) octoid
d) none of the mentioned
Answer: b
Clarification: The length of teeth along the cone distance is face width.
The sharp corner orming the outside diameter is crown.

9. The angle of a cone whose elements are tangent to a sphere containing a trace of the pitch circle is
a) crown
b) back cone
c) octoid
d) none of the mentioned
Answer: b
Clarification: The angle between elements of the root cone and pitch cone is dedendum angle.
The angle of a cone whose elements are tangent to a sphere containing a trace of the pitch circle is back cone.

10. The angle between elements of the root cone and pitch cone is
a) addendum angle
b) dedendum angle
c) spiral angle
d) none of the mentioned
Answer: b
Clarification: The angle between elements of the root cone and pitch cone is dedendum angle.
The angle of a cone whose elements are tangent to a sphere containing a trace of the pitch circle is back cone.

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250+ TOP MCQs on Simple Pendulum and Answers

Machine Kinematics Multiple Choice Questions on “Simple Pendulum”.

1. The acceleration of the particle moving with simple harmonic motion is inversely proportional to the displacement of the particle from the mean position.
a) True
b) False
Answer: b
Clarification: The acceleration of the particle moving with simple harmonic motion is directly proportional to the displacement of the particle from the mean position.

2. In order to double the period of a simple pendulum, the length of the string should be
a) halved
b) doubled
c) quadrupled
d) none of the mentioned
Answer: c
Clarification: Periodic time, t_p = 2п√L/g
So, if period is doubled, then length should be quadrupled

3. The equivalent length of simple pendulum depends upon the distance between the point of the suspension and the center of gravity.
a) True
b) False
Answer: a
Clarification: None

4. Which of the following statement is correct?
a) The periodic time of a particle moving with simple harmonic motion is the time taken by a particle for one complete oscillation.
b) The periodic time of a particle moving with simple harmonic motion is directly proportional to its angular velocity.
c) The velocity of a particle moving with simple harmonic motion is zero at the mean position.
d) The acceleration of the particle moving with simple harmonic motion is maximum at the mean position.
Answer: a
Clarification: The time taken for one complete revolution of the particle is called periodic time.

5. The periodic time of a compound pendulum is …….. when the distance between the point of suspension and the center of gravity is equal to the radius of gyration of the body about its center of gravity.
a) zero
b) minimum
c) maximum
d) none of the mentioned
Answer: b
Clarification: 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 compound pendulum.

6. In a simple harmonic motion, the velocity vector with respect to displacement vector
a) is in phase
b) leads by 90⁰
c) leads by 180⁰
d) lags by 90⁰
Answer: d
Clarification: None

7. The distance between the center of suspension and center of percussion is equal to the equivalent length of a simple pendulum.
a) True
b) False
Answer: a
Clarification: The periodic time and frequency of oscillation of a simple pendulum depends only upon its length and acceleration due to gravity.

8. The center of suspension and center of percussion are not interchangeable.
a) True
b) False
Answer: b
Clarification: The distance between the center of suspension and center of percussion is equal to the equivalent length of a simple pendulum.

9. When the body is suspended at the point of suspension, its periodic time and frequency will be _____________ as compared to the body suspended at the point of percussion.
a) same
b) two times
c) four times
d) eight times
Answer: a
Clarification: The distance between the center of suspension and center of percussion is equal to the equivalent length of a simple pendulum.

10. Bifilar suspension method is used to find the
a) angular acceleration of the body
b) moment of inertia of the body
c) periodic time of the body
d) frequency of vibration of the body
Answer: b
Clarification: None

250+ TOP MCQs on Application of Kutzbach Criterion to Plane Mechanisms and Answers

Machine Kinematics Mcqs on “Application of Kutzbach Criterion to Plane Mechanisms”.

1. In its simplest form, a cam mechanism consists of following number of links
a) 1
b) 2
c) 3
d) 4

Answer: c
Clarification: Cam consists of 3 links.

2. Which of the following mechanisms produces mathematically an exact straight line motion?
a) Grasshopper mechanism
b) Watt mechanism
c) Peaucellier’s mechanism
d) Tchabichiff mechanism

Answer: c
Clarification: Peaucellier’s mechanism gives straight line motion.

3. In a mechanism, usually one link is fixed. If the fixed link is changed in a kinematic chain, then relative motion of other links
a) will remain same
b) will change
c) will not occur
d) none of the mentioned

Answer: a
Clarification: There will be no change.

4. A kinematic chain requires at least
a) 2 links and 3 turning pairs
b) 3 links and 4 turning pairs
c) 4 links and 4 turning pairs
d) 5 links and 4 turning pairs

Answer: c
Clarification: In a Kinematic chain, the number of links should be equal to the number of turning pairs.

5. In a drag link quick return mechanism, the shortest link is always fixed. The sum of the shortest and longest link is
a) equal to sum of other two
b) greater than sum of other two
c) less than sum of other two
d) none of the mentioned

Answer: c
Clarification: None

6. The following is the inversion of slider crank chain mechanism
a) whitworth quick return mechanism
b) hand pump
c) oscillating cylinder engine
d) all of the mentioned

Answer: d
Clarification: None

7. Kinematic pairs are those which have
a) two elements held together mechanically
b) two elements having relative motion
c) two elements having Coroli’s component
d) none of the mentioned

Answer: b
Clarification: Kinematic pair is ajoint of two elements that permits relative motion.

8. According to criterion of constraint by A.W. Klein
a) J + 1/2 H = 3/2L – 2
b) H + 1/2J = 2/3L – 2
c) J + 1/2H = 3/2L – 1
d) J + 3/2H = 1/2L – 2

Answer: a
Clarification: The criterion for a chain to be constrained is
J + 1/2 H = 3/2L – 2

9. A quarternary joint is equivalent to
a) one binary joint
b) two binary joints
c) three binary joints
d) four binary joints

Answer: c
Clarification: None

10. A typewriter mechanism has 7 number of binary joints, six links and none of higher pairs. The mechanism is
a) kinematically sound
b) not sound
c) soundness would depend upon which link is kept fixed
d) none of the mentioned

Answer: a
Clarification: J + 1/2 H = 3/2L – 2
or, 7 + 0 = 3/2 x 6 -2
or, 7 = 7

Hence, it is Kinematically sound.

250+ TOP MCQs on Velocity of a Point on a Link by Relative Velocity Method and Answers

Machine Kinematics Multiple Choice Questions on ” Velocity of a Point on a Link by Relative Velocity Method”.

1. The instantaneous centre is a point which is always fixed.
a) True
b) False
Answer: b
Clarification: The instantaneous center is not always fixed.

2. The angular velocity of a rotating body is expressed in terms of
a) revolution per minute
b) radians per second
c) any one of the mentioned
d) none of the mentioned
Answer: c
Clarification: Angular velocity is expressed both as revolution per minute and radians per second.

3. The linear velocity of a rotating body is given by the relation
a) v = rω
b) v = r/ω
c) v = ω/r
d) v = ω²/r
Answer: a
Clarification: The linear velocity of a rotating body is given by the relation v = rω
The linear acceleration of a rotating body is given by the relation a = rα.

4. The linear acceleration of a rotating body is given by the relation
a) a = rα
b) a = r/α
c) a = α/r
d) a = α²/r
Answer: a
Clarification: The linear velocity of a rotating body is given by the relation v = rω
The linear acceleration of a rotating body is given by the relation a = rα.

5. The relation between linear velocity and angular velocity of a cycle
a) exists under all conditions
b) does not exist under all conditions
c) exists only when it does not slip
d) exists only when it moves on horizontal plane
Answer: a
Clarification: None.

6. The velocity of piston in a reciprocating pump mechanism depends upon
a) angular velocity of the crank
b) radius of the crank
c) length of the connecting rod
d) all of the mentioned
Answer: d
Clarification: None.

7. The linear velocity of a point B on a link rotating at an angular velocity ω relative to another point A on the same link is
a) ω²AB
b) ωAB
c) ω(AB)²
d) ω/AB
Answer: b
Clarification: None.

8. The linear velocity of a point relative to another point on the same link is ……….. to the line joining the points.
a) perpendicular
b) parallel
c) at 45⁰
d) none of the mentioned
Answer: a
Clarification: The total linear acceleration of a particle can be obtained by combining the two mutually perpendicular accelerations.

9. According to Kennedy’s theorem the instantaneous centres of three bodies having relative motion lie on a
a) curved path
b) straight line
c) point
d) none of the mentioned
Answer: b
Clarification: The Aronhold Kennedy’s theorem states that if three bodies move relatively to each other, they have three instantaneous centres and lie on a straight line.

10. The instantaneous centers of a slider moving in a linear guide lies at
a) pin joints
b) their point of contact
c) infinity
d) none of the mentioned
Answer: c
Clarification: The instantaneous centers of a slider moving in a linear guide lies at infinity.
The instantaneous centers of a slider moving in a curved surface lies at the center of curvature.

250+ TOP MCQs on Laws of Fluid Friction and Answers

Machine Kinematics Multiple Choice Questions on “Laws of Fluid Friction”.

1. A multiple disc clutch has five plates having four pairs of active friction surfaces. If the intensity of pressure is not to exceed 0.127 N/mm², find the power transmitted at 500 r.p.m. The outer and inner radii of friction surfaces are 125 mm and 75 mm respectively. Assume uniform wear and take coefficient of friction = 0.3.
a) 17.8 kW
b) 18.8 kW
c) 19.8 kW
d) 20.8 kW
Answer: b
Clarification: n₁ + n₂ = 5 ; n = 4 ; p = 0.127 N/mm² ; N = 500 r.p.m. or ω = 2π × 500/60 = 52.4 rad/s ; r₁ = 125 mm ; r₂ = 75 mm ; μ = 0.3
Since the intensity of pressure is maximum at the inner radius r₂, therefore
p.r₂ = C or C = 0.127 × 75 = 9.525 N/mm
We know that axial force required to engage the clutch,
W = 2 π C (r₁ – r₂) = 2 π × 9.525 (125 – 75) = 2990 N
and mean radius of the friction surfaces,
R = r₁ + r₂/2 = 125 + 75/2 = 100 mm = 0.1 m
We know that torque transmitted,
T = n.μ.W.R = 4 × 0.3 × 2990 × 0.1 = 358.8 N-m
∴ Power transmitted,
P = T.ω = 358.8 × 52.4 = 18 800 W = 18.8 kW.

2. A single plate clutch, with both sides effective, has outer and inner diameters 300 mm and 200 mm respectively. The maximum intensity of pressure at any point in the contact surface is not to exceed 0.1 N/mm². If the coefficient of friction is 0.3, determine the power transmitted by a clutch at a speed 2500 r.p.m.
a) 61.693 kW
b) 71.693 kW
c) 81.693 kW
d) 91.693 kW
Answer: a
Clarification: Given : d₁ = 300 mm or r₁ = 150 mm ; d₂ = 200 mm or r₂ = 100 mm ; p = 0.1 N/mm² ; μ = 0.3 ; N = 2500 r.p.m. or ω = 2π × 2500/60 = 261.8 rad/s
Since the intensity of pressure ( p) is maximum at the inner radius (r₂), therefore for uniform wear,
p.r₂ = C or C = 0.1 × 100 = 10 N/mm
We know that the axial thrust,
W = 2 π C (r₁ – r₂) = 2 π × 10 (150 – 100) = 3142 N
and mean radius of the friction surfaces for uniform wear,
R = r₁ + r₂/2 = 150 + 100/2 = 125 mm = 0.125m
We know that torque transmitted,
T = n.μ.W.R = 2 × 0.3 × 3142 × 0.125 = 235.65 N-m …( n = 2,for both sides of plate effective)
∴ Power transmitted by a clutch,
P = T.ω = 235.65 × 261.8 = 61 693 W = 61.693 kW.

3. A 60 mm diameter shaft running in a bearing carries a load of 2000 N. If the coefficient of friction between the shaft and bearing is 0.03, find the power transmitted when it runs at 1440 r.p.m.
a) 171.4 W
b) 271.4 W
c) 371.4 W
d) 471.4 W
Answer: b
Clarification: Given : d = 60 mm or r = 30 mm = 0.03 m ; W = 2000 N ; μ = 0.03 ; N = 1440 r.p.m.
or ω = 2π × 1440/60 = 150.8 rad/s
We know that torque transmitted,
T = μ.W.r = 0.03 × 2000 × 0.03 = 1.8 N-m
∴ Power transmitted, P = T.ω = 1.8 × 150.8 = 271.4 W.

4. The force of friction is inversely proportional to the normal load between the surfaces.
a) True
b) False
Answer: b
Clarification: The force of friction is directly proportional to the normal load between the surfaces.

5. The force of friction is dependent of the area of the contact surface for a given normal load.
a) True
b) False
Answer: b
Clarification: The force of friction is independent of the area of the contact surface for a given normal load.

6. The force of friction depends upon the material of which the contact surfaces are made.
a) True
b) False
Answer: a
Clarification: Following are the laws of solid friction :
1. The force of friction is directly proportional to the normal load between the surfaces.
2. The force of friction is independent of the area of the contact surface for a given normal load.
3. The force of friction depends upon the material of which the contact surfaces are made.
4. The force of friction is independent of the velocity of sliding of one body relative to the other body.

7. The force of friction is dependent of the velocity of sliding of one body relative to the other body.
a) True
b) False
Answer: b
Clarification: The force of friction is independent of the velocity of sliding of one body relative to the other body.

8. The force of friction is almost dependent of the load.
a) True
b) False
Answer: b
Clarification: The force of friction is almost independent of the load.

9. The force of friction is dependent of the substances of the bearing surfaces.
a) True
b) False
Answer: b
Clarification: The force of friction is independent of the substances of the bearing surfaces.

10. The force of friction is _____________ for different lubricants.
a) same
b) different
c) zero
d) none of the mentioned
Answer: a
Clarification: The force of friction is different for different lubricants.