Engineering Questions with Answers - Multiple Choice Questions
Machine Kinematics Questions and Answers – Velocity in Mechanisms – 2
1 - Question
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
View Answer
Answer: b
Explanation: 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 - Question
In a pantograph, all the pairs are
a) turning pairs
b) sliding pairs
c) spherical pairs
d) self-closed pairs
View Answer
Answer: a
Explanation: 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 - Question
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
View Answer
Answer: b and c
Explanation: 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 - Question
Scott Russel’s mechanism is made up of sliding pair.
a) True
b) False
View Answer
Answer: a
Explanation: Exact straight line motion mechanisms consists of one sliding pair. The Scott Russell’s mechanism is of this type.
5 - Question
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
View Answer
Answer: d
Explanation: 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 - Question
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
View Answer
Answer: d
Explanation: 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 - Question
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
View Answer
Answer: c
Explanation: 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 - Question
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
View Answer
Answer: c
Explanation: 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 - Question
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
View Answer
Answer: c
Explanation: 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 - Question
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
View Answer
Answer: d
Explanation: 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.