Category: Machine Kinematics Objective Questions

250+ TOP MCQs on Mechanism – 1 and Answers

Machine Kinematics Multiple Choice Questions on “Mechanism – 1”.

1. A type-writer constitutes a machine.
a) True
b) False
Answer: b
Clarification: When a mechanism is required to transmit power or to do some particular type of work, it then becomes a machine.But in case of a typewriter there is no case of power transmission. Hence it is not a machine.

2. The method of obtaining different mechanisms by fixing in turn different links in a kinematic chain, is known as
a) structure
b) machine
c) inversion
d) compound mechanism
Answer: c
Clarification: We can obtain as many mechanisms as the number of links in kinematic chain by fixing, in turn,different links in a kinematic chain. This method is known as inversion of the mechanism.

3. If the number of links in a mechanism are equal to l, then the number of possible inversions are equal to
a) l – 2
b) l – 1
c) l
d) l + 1
Answer: c
Clarification: Whatever is the number of links in a mechanism, only that much number of inversion can be obtained.

4. Which of the following statement is correct as regard to the difference between a machine and a structure?
a) The parts of a machine move relative to one another, whereas the members of a structure do not move relative to one another.
b) The links of a machine may transmit both power and motion, whereas the members of a structure transmit forces only.
c) A machine transforms the available energy into some useful work, whereas in a structure no energy is transformed into useful work.
d) all of the mentioned
Answer: d
Clarification: None

5. A kinematic chain is known as a mechanism when
a) none of the links is fixed
b) one of the links is fixed
c) two of the links are fixed
d) none of the mentioned
Answer: b
Clarification: When one of the links of a kinematic chain is fixed, the chain is known as mechanism.

6. The inversion of a mechanism is
a) changing of a higher pair to a lower pair
b) turning its upside down
c) obtained by fixing different links in a kinematic chain
d) obtained by reversing the input and output motion
Answer: c
Clarification: We can obtain as many mechanisms as the number of links in kinematic chain by fixing, in turn,different links in a kinematic chain. This method is known as inversion of the mechanism.

7. The Grubler’s criterion for determining the degrees of freedom (n) of a mechanism having plane motion is
a) n = (l – 1) – j
b) n = 2(l – 1) – 2j
c) n = 3(l – 1) – 2j
d) n = 4(l – 1) – 3j
Answer: c
Clarification: None

8. The mechanism forms a structure, when the number of degrees of freedom (n) is equal to
a) 0
b) 1
c) 2
d) -1
Answer: a
Clarification: A structure can be formed only when the number of degrees of freedom is zero.

9. In a four bar chain or quadric cycle chain
a) each of the four pairs is a turning pair
b) one is a turning pair and three are sliding pairs
c) two are turning pairs and two are sliding pairs
d) three are turning pairs and one is a sliding pair
Answer: a
Clarification: Four bar chain or quadric cycle chain consists of four links, each of them forms a turning pair.

10. The mechanism in which two are turning pairs and two are sliding pairs, is called a
a) double slider crank chain
b) elliptical trammel
c) scotch yoke mechanism
d) all of the mentioned
Answer: d
Clarification: A double slider crank chain consists of two sliding pairs and two turning pairs. The inversions of a double slider crank chain are as follows:
a) elliptical trammel
b) scotch yoke mechanism
c) oldham’s coupling

250+ TOP MCQs on Velocity in Mechanisms – 2 and Answers

Machine Kinematics Multiple Choice Questions on “Velocity in Mechanisms – 2”.

1. The coriolis component of acceleration exists whenever a point moves along a path that has
a) linear displacement
b) rotational motion
c) gravitational acceleration
d) tangential acceleration
Answer: b
Clarification: When a point on one link is sliding along another rotating link such as in quick return motion mechanism, then Coriolis component of acceleration must be taken into account. It means for Coriolis component, rotational motion is required.

2. In a pantograph, all the pairs are
a) turning pairs
b) sliding pairs
c) spherical pairs
d) self-closed pairs
Answer: a
Clarification: Pantograph is an instrument used to reproduce to an enlarged or a reduced scale and as exactly as possible the path described by a given point. It consists of bars connected by turning pairs.

3. Which of the following mechanism is made up of turning pairs?
a) Scott Russel’s mechanism
b) Peaucellier’s mechanism
c) Hart’s mechanism
d) All of the mentioned
Answer: b and c
Clarification: Exact straight line motion mechanisms are made up of turning pairs. These mechanisms are as follows:
a) Peaucellier’s mechanism
b) Hart’s mechanism.

4. Scott Russel’s mechanism is made up of sliding pair.
a) True
b) False
Answer: a
Clarification: Exact straight line motion mechanisms consists of one sliding pair. The Scott Russell’s mechanism is of this type.

5. An exact straight line motion mechanism is a
a) Scott-Russell’s mechanism
b) Hart’s mechanism
c) Peaucellier’s mechanism
d) All of the mentioned
Answer: d
Clarification: All the mechanisms mentioned above consists of exact straight line motion. Scott-Russell’s mechanism consists of sliding pair whereas Peaucellier’s mechanism and Hart’s mechanism consists of turning pair.

6. Which of the following mechanism is an approximate straight line motion mechanism?
a) Watt’s mechanism
b) Grasshopper mechanism
c) Robert’s mechanism
d) All of the mentioned
Answer: d
Clarification: The mechanism that are approximate straight line motion are as follows:
a) Watt’s mechanism
b) Scott-Russell’s mechanism
c) Grasshopper mechanism
d) Robert’s mechanism
e) Tehebicheff’s mechanism.

7. The fundamental equation for correct steering is
a) sinɸ + sinα = b/c
b) cosɸ – sinα = c/b
c) cotɸ – cotα = c/b
d) tanɸ + cotα = b/c
Answer: c
Clarification: The condition for correct steering is that all the four wheels must turn about the same instantaneous centre.
The fundamental equation for correct steering is
cotɸ – cotα = c/b

where ɸ and α = Angle through which the axix of the outer wheel and inner wheel turns respectively
c = Distance between the pivots of the front axles
b = Wheel base.

8. The condition for correct steering of a Davis steering is
a) sinα = b/c
b) cosα = c/b
c) tanα = c/2b
d) cotα = c/2b
Answer: c
Clarification: In case of Davis steering gear, the condition for correct steering is
tanα = c/2b
where α = Angle of inclination of the links to the vertical.

9. The driving and driven shafts connected by a Hooke’s joint will have equal speeds, if
a) cosϴ = sinα
b) sinϴ = √tanα
c) tanϴ = √cosα
d) cotϴ = cosα
Answer: c
Clarification: A Hooke’s joint is used to connect two shafts, which are intersecting at a small angle. The speed of the driving and driven shafts will be equal, when
tanϴ = √cosα.

10. The Ackerman steering gear mechanism is preferred to the Davis steering gear mechanism because
a) whole of the mechanism in the Ackerman steering gear is on the back of the front wheels
b) the Ackerman steering gear consists of turning pairs
c) the Ackerman steering gear is most economical
d) both a and b
Answer: d
Clarification: The Acerman steering gear mechanism is much simpler than Davis gear. The whole mechanism of Ackerman steering gear is on the back of the front wheels, whereas in Davis steering gear, it is in front of the wheels. The Ackerman steering gear consists of turning pairs, whereas Davis steering gear consists of sliding members.

250+ TOP MCQs on Friction Between Lubricated Surfaces and Answers

Machine Kinematics Multiple Choice Questions on “Friction Between Lubricated Surfaces”.

1. _____________ is the friction, experienced by a body, due to the motion of rotation as in case of foot step bearings.
a) Pivot friction
b) Solid friction
c) Dry friction
d) None of the mentioned
Answer: a
Clarification: Pivot friction is the friction, experienced by a body, due to the motion of rotation as in case of foot step bearings.

2. ______________ is the friction experienced between two dry and unlubricated surfaces in contact.
a) Pivot friction
b) Solid friction
c) Boundary friction
d) None of the mentioned
Answer: b
Clarification: The friction experienced between two dry and unlubricated surfaces in contact is known as dry or solid friction. It is due to the surface roughness.

3. ______________ is the friction, experienced between the rubbing surfaces, when the surfaces have a very thin layer of lubricant.
a) Pivot friction
b) Solid friction
c) Boundary friction
d) None of the mentioned
Answer: c
Clarification: Boundary friction It is the friction, experienced between the rubbing surfaces, when the surfaces have a very thin layer of lubricant. The thickness of this very thin layer is of the molecular dimension.

4. _____________ is the friction, experienced between the rubbing surfaces, when the surfaces have a thick layer of the lubricant.
a) Fluid friction
b) Solid friction
c) Boundary friction
d) None of the mentioned
Answer: a
Clarification: Fluid friction is the friction, experienced between the rubbing surfaces, when the surfaces have a thick layer of the lubricant. In this case, the actual surfaces do not come in contact and thus do not rub against each other.

5. _____________ is a measure of the resistance offered to the sliding one layer of the lubricant over an adjacent layer.
a) Viscocity
b) Density
c) Oiliness
d) None of the mentioned
Answer: a
Clarification: The viscosity is a measure of the resistance offered to the sliding one layer of the lubricant over an adjacent layer.

6. The absolute viscosity of a lubricant may be defined as the force required to cause a plate of unit area to slide with unit velocity relative to a parallel plate.
a) True
b) False
Answer: a
Clarification: The absolute viscosity of a lubricant may be defined as the force required to cause a plate of unit area to slide with unit velocity relative to a parallel plate, when the two plates are separated by a layer of lubricant of unit thickness.

7. The lubricant which gives ______________ force of friction is said to have greater oiliness.
a) greater
b) lesser
c) similar
d) none of the mentioned
Answer: b
Clarification: The lubricant which gives lower force of friction is said to have greater oiliness.

8. When the lubricants are smeared on two different surfaces, it is found that the force of friction with one lubricant is different than that of the other.
a) True
b) False
Answer: a
Clarification: When these lubricants are smeared on two different surfaces, it is found that the force of friction with one lubricant is different than that of the other. This difference is due to the property of the lubricant known as oiliness.

250+ TOP MCQs on Chain Drives and Answers

Machine Kinematics Multiple Choice Questions on “Chain Drives”.

1. What is the purpose of using steel chains?
a) To avoid slipping
b) To avoid friction
c) To avoid accelerated motion
d) To avoid jerks
Answer: a
Clarification: In belt and rope drives, it is observed that slipping may take place. In order to avoid the issue of slipping, steel chains are being used.

2. The chains are made up of rigid links which are hinged together in order to avoid flexibility for warping around the driving and driven wheels.
a) True
b) False
Answer: b
Clarification: The chains are made up of rigid links which are hinged together in order to provide the necessary flexibility for warping around the the two sets of wheels, i.e. driving and driven wheels.

3. The toothed wheels in chain drives are known as ______
a) Sprockets
b) Sprockers
c) V-belt
d) V- chain
Answer: a
Clarification: The wheels and the chain are subjected to a constraint to move together without slipping and ensures perfect velocity ratio. The toothed wheels are known as sprocket wheels or sprockets.

4. Which of the following is true regarding chain drives?
a) The chain drives may be used when the distance between the shafts is less
b) The production cost of chains is relatively low
c) The chain drive needs low maintenance
d) The chain drive has no velocity fluctuations
Answer: b
Clarification: The chain drives may be used when the distance between the shafts is less. This is an advantage of using a chain drive over belt or rope drives.

5. The distance between hinge centres of two corresponding links is known as _______
a) Pitch
b) Pitch circle diameter
c) Sprocket length
d) Sprocker diameter
Answer: a
Clarification: Pitch ‘p’ of the chain is the linear distance between the hinge centre of a link and the corresponding hinge centre of the adjacent link. It is usually denoted by p.

6. In the figure given below, what the quantity ‘p’ is known as _________
machine-kinematics-questions-answers-chain-drives-q6
a) Pitch
b) Pitch circle diameter
c) Sprocket length
d) Sprocker diameter
Answer: a
Clarification: In the given figure the quantity p is the Pitch. Pitch of the chain is the distance between the hinge centre of a link and the corresponding hinge centre of the adjacent link.

7. The diameter of the circle on which the hinge centres of the chain lie is known as _______
a) Pitch
b) Pitch circle diameter
c) Sprocket length
d) Sprocker diameter.
Answer: a
Clarification: Pitch circle diameter of the chain sprocket is the diameter of the circle on which the hinge centres of the chain lie, when the chain is wrapped round a sprocket.

8. Pitch of the chain lies on the arc of the pitch circle.
a) True
b) False
Answer: b
Clarification: Since the links of the chain are rigid, therefore pitch of the chain does not lie on the arc of the pitch circle. Thus, the given statement is false.

9. Which of the following chains fall under the category of hoisting and hauling chains?
a) Chain with oval links
b) Closed joint chain
c) Detachable chain
d) Block chain
Answer: a
Clarification: Chains with oval links are used only at low speeds such as in chain hoists and in anchors for marine works. Hence it falls under the above mentioned category.

10. Which of the following chain is used to provide elevation continuosly?
a) Conveyor chains
b) Power transmitting chains
c) Hoisting chains
d) Hauling chains
Answer: a
Clarification: Conveyer chains are are used for elevating and conveying the materials continuously. The conveyor chains are of the following two types : Detachable or hook joint type chain and Closed joint type chain.

11. Which of the following chains are used for transmission of power, when the distance between the centres of shafts is short?
a) Chain with oval links
b) Closed joint chain
c) Detachable chain
d) Block chain
Answer: d
Clarification: Block chains are used for transmission of power, when the distance between the centres of shafts is relatively short. These chains provide efficient lubrication.

250+ TOP MCQs on Types of Gears and Answers

Machine Kinematics Multiple Choice Questions on “Types of Gears”.

1. The gears used for parallel shaft arrangement are
a) mitre gear
b) face gear
c) spur gears on helical gears
d) none of the mentioned
Answer: c
Clarification: Bevel gears are the gears used for intersecting shaft arrangement.
The gears used for parallel shaft arrangement are spur gears on helical gears.

2. _____________ are the gears used for intersecting shaft arrangement.
a) bevel gears
b) beveloid gears
c) mitre gears
d) none of the mentioned
Answer: a
Clarification: Bevel gears are the gears used for intersecting shaft arrangement.
The gears used for parallel shaft arrangement are spur gears on helical gears.

3. ________________ are gears used for skew arrangement.
a) spur gears on helical gears
b) helical, worm, or hypoid gears
c) mitre gears
d) none of the mentioned
Answer: b
Clarification: Helical, worm, or hypoid gears are gears used for skew arrangement.
Bevel gears are the gears used for intersecting shaft arrangement.

4. Bevel gears used for connecting intersecting shafts at 900 and having speed ratio 1 : 1 is known as
a) bevel gears
b) beveloid gears
c) mitre gears
d) none of the mentioned
Answer: c
Clarification: Bevel gears used for connecting intersecting shafts at 900 and having speed ratio 1 : 1 is known as mitre gears.
Bevel gears with basic pressure angle of 200 with long and short addendums for ratios other than 1:1 to avoid undercut pinions and to increase strength are gleason bevel gears.

5. Tapered involute gears which can couple intersecting shafts, skew shafts, and parallel shafts are known as
a) bevel gears
b) beveloid gears
c) mitre gears
d) none of the mentioned
Answer: b
Clarification: Tapered involute gears which can couple intersecting shafts, skew shafts, and parallel shafts are known as beveloid gears.
The gears used for parallel shaft arrangement are spur gears on helical gears.

6. Gears having teeth cut on the rotating face plane of the gear and mate with standard involute spur gears are known as
a) mitre gear
b) face gear
c) spur gears on helical gears
d) none of the mentioned
Answer: b
Clarification: Worm gears are used for obtaining large speed reduction between non-intersecting shafts making an angle of 900 with each other.
Gears having teeth cut on the rotating face plane of the gear and mate with standard involute spur gears are known as face gears.

7. ____________ gears are used for obtaining large speed reduction between non-intersecting shafts making an angle of 900 with each other.
a) worm gears
b) beveloid gears
c) mitre gears
d) none of the mentioned
Answer: a
Clarification: Worm gears are used for obtaining large speed reduction between non-intersecting shafts making an angle of 900 with each other.
Gears having teeth cut on the rotating face plane of the gear and mate with standard involute spur gears are known as face gears.

8. Bevels connecting shafts other than 900 are
a) worm gears
b) angular bevel gears
c) mitre gears
d) none of the mentioned
Answer: b
Clarification: Bevels connecting non-intersecting shafts are skew bevel gears.
Bevels connecting shafts other than 900 are angular bevel gears.

9. Bevels connecting non-intersecting shafts are
a) skew bevel gears
b) angular bevel gears
c) mitre gears
d) none of the mentioned
Answer: a
Clarification: Bevels connecting non-intersecting shafts are skew bevel gears.
Bevels connecting shafts other than 900 are angular bevel gears.

10. Bevel gears with basic pressure angle of 200 with long and short addendums for ratios other than 1:1 to avoid undercut pinions and to increase strength are
a) skew bevel gears
b) angular bevel gears
c) gleason bevel gears
d) none of the mentioned
Answer: c
Clarification: Bevel gears used for connecting intersecting shafts at 900 and having speed ratio 1 : 1 is known as mitre gears.
Bevel gears with basic pressure angle of 200 with long and short addendums for ratios other than 1:1 to avoid undercut pinions and to increase strength are gleason bevel gears.

250+ TOP MCQs on Velocity and Acceleration of a Particle Moving with Simple Harmonic Motion and Answers

Machine Kinematics Questions on “Velocity and Acceleration of a Particle Moving with Simple Harmonic Motion”.

1. A body is said to vibrate with simple harmonic motion if its acceleration is proportional to the distance from the mean position.
a) True
b) False

Answer: a
Clarification: A body is said to move with simple harmonic motion, if it satisfies the following two conditions:
a) Its acceleration is always directed towards the center, known as point of reference or mean position.
b) Its acceleration is proportional to the distance from that point.

2. The maximum displacement of a body, from its mean position is called amplitude.
a) True
b) False

Answer: a
Clarification: The time taken for one complete revolution of the particle is called periodic time.
The maximum displacement of a body from its mean position is called amplitude.

3. Frequency of vibrations is usually expressed in
a) number of cycles per hour
b) number of cycles per minute
c) number of cycles per second
d) none of the mentioned

Answer: c
Clarification: The number of cycles per second is called frequency. It is the reciprocal of periodic time.

4. The amplitude of vibrations is always ______________ the radius of the circle.
a) equal to
b) less than
c) greater than
d) none of the mentioned

Answer: a
Clarification: None.

5. The time taken by a particle for one complete oscillation is known as periodic time.
a) True
b) False

Answer: a
Clarification: The time taken for one complete revolution of the particle is called periodic time.
The maximum displacement of a body from its mean position is called amplitude.

6. The periodic time is given by
a) ω/2п
b) 2п/ω
c) ω x 2п
d) п/ω

Answer: b
Clarification: Periodic time, tp = 2п/ω seconds
where ω = Angular velocity of the particle in rad/s.

7. When a body moves with simple harmonic motion, the product of its periodic time and frequency is equal to
a) zero
b) one
c) п/2
d) п

Answer: b
Clarification: The number of cycles per second is called frequency. It is the reciprocal of periodic time. Hence, when it is multiplied it is equal to one.

8. The acceleration of the particle moving with simple harmonic motion is ____________ at the mean position.
a) zero
b) minimum
c) maximum
d) none of the mentioned

Answer: a
Clarification: The acceleration of a body is zero at the mean position and maximum when x = r.

9. The maximum velocity of a particle moving with simple harmonic motion is
a) ω
b) ωr
c) ω2r
d) ω/r

Answer: b
Clarification:The velocity of a moving body with simple harmonic motion at any instant is given by
v = ω√r2 – x2
The velocity is maximum at the mean position i.e. when x = 0.

Hence, v = ωr.

10. When a particle moves round the circumference of a circle of radius r with ω rad/s, then its maximum acceleration is ω2r.
a) True
b) False

Answer: a
Clarification: The acceleration of a body moving with simple harmonic motion at any instant is given by
a = ω2r.

11. If a simple pendulum oscillates with an amplitude 50 mm and time period 2s, then its maximum velocity is
a) 0.1 m/s
b) 0.15 m/s
c) 0.8 m/s
d) 0.16 m/s

Answer: b
Clarification: Maximum velocity vmax = ωA where ‘ω’ is the angular frequency and ‘A’ is the amplitude. Therefore vmax = (2π/T)A = (2π/2)×50×10-3 = 0.157 m/s.

12. A particle executes linear simple harmonic motion with an amplitude of 2 cm. When the particle is at 1 cm from the mean position, the magnitude of its velocity is equal to that of its acceleration. Then its time period in seconds is
a) 1/ 2π√3
b) 2π√3
c) 2π/√3
d) √3/2π

Answer: b
Clarification: The magnitudes of the velocity and acceleration of the particle when its displacement is ‘y’ are ω√(A2 –y2) and ω2y respectively. Equating them, ω√(A2 –y2) = ω2y, from which ω = [√(A2 –y2)]/y = √(4 –1) = √3. Period T = 2π/ω = 2π/√3.

13. Suppose you place a sphere of mass ‘m’ and radius ‘r’ inside a smooth, heavy hemispherical bowl of radius of 37r placed on a horizontal table. If the sphere is given a small displacement, what is its period of oscillation?
a) 2π√(m/37rg)
b) 2π√(m/rg)
c) 12π√(r/g)
d) 2π√(r/g)

Answer: c
Clarification: The arrangement depicted in this question is similar to that of a simple pendulum. Instead of the usual string, you have a concave surface to confine the bob (sphere) to its path along the arc of a circle. The usual expression for the period, T = 2π√(L/g) holds here also, where the length L = 36r since the length of the pendulum is measured from the centre of gravity of the bob. The point of ‘suspension’ is evidently at the centre of the hemispherical bowl. The correct option is 12π√(r/g).

14. The instantaneous displacement of a simple harmonic oscillator is given by y = A cos(ωt + π/4). Its speed will be maximum at the time
a) 2π/ω
b) ω/2π
c) ω/π
d) π/4ω

Answer: d
Clarification: The velocity is the time derivative of displacement: v = dy/dt = -Aω(sin ωt + π/4). Its maximum magnitude equal to Aω is obtained when ωt = π/4, from which t = π/4ω.

15. A particle of mass 5 g is executing simple harmonic motion with an amplitude 0.3 m and time period π/5 s. The maximum value of the force acting on the particle is
a) 5 N
b) 4 N
c) 0.5 N
d) 0.15 N

Answer: d
Clarification: T = 2π√(m/k) where ‘k’ is the force constant, the solution becomes quite easy. From this, k = 4π2m/T2 = 4π2 ×5×10-3/(π/5)2 = 0.5. Since ‘k’ is the force for unit displacement, the maximum force is k times the maximum displacement (amplitude). Therefore maximum force = kA = 0.5×0.3 = 0.15N.