Engineering Questions with Answers - Multiple Choice Questions

Machine Kinematics MCQ– Straight Line Mechanism

1 - Question

A double universal joint is used to connect two shafts in the same plane. The intermediate shaft is inclined at an angle of 20° to the driving shaft as well as the driven shaft. Find the maximum speed of the intermediate shaft if the driving shaft has a constant speed of 500 r.p.m.
a) 532.1 r.p.m
b) 469.85 r.p.m
c) 566.25 r.p.m
d) 441.5 r.p.m.

View Answer

Answer: a
Explanation: Given α = 20° ; NA = 500 r.p.m.
Let A, B and C are the driving shaft, intermediate shaft and driven shaft respectively. We know that for the driving shaft (A) and intermediate shaft (B),
Maximum speed of the intermediate shaft,
NB(max) = NA/cosα = 500/cos 20°= 532.1 r.p.m.




2 - Question

A double universal joint is used to connect two shafts in the same plane. The intermediate shaft is inclined at an angle of 20° to the driving shaft as well as the driven shaft. Find the minimum speed of the intermediate shaft if the driving shaft has a constant speed of 500 r.p.m.
a) 532.1 r.p.m
b) 469.85 r.p.m.
c) 566.25 r.p.m.
d) 441.5 r.p.m.

View Answer

Answer: b
Explanation: Given α = 20° ; NA = 500 r.p.m.
Let A, B and C are the driving shaft, intermediate shaft and driven shaft respectively. We know that for the driving shaft (A) and intermediate shaft (B),
minimum speed of the intermediate shaft,
NB(min) = NAcosα = 500 × cos 20° = 469.85 r.p.m.




3 - Question

A double universal joint is used to connect two shafts in the same plane. The intermediate shaft is inclined at an angle of 20° to the driving shaft as well as the driven shaft. Find the maximum speed of the driven shaft if the driving shaft has a constant speed of 500 r.p.m.
a) 532.1 r.p.m
b) 469.85 r.p.m.
c) 566.25 r.p.m.
d) 441.5 r.p.m.

View Answer

Answer: c
Explanation: Given α = 20° ; NA = 500 r.p.m.
Let A, B and C are the driving shaft, intermediate shaft and driven shaft respectively. We know that for the driving shaft (A) and intermediate shaft (B),
Maximum speed of the driven shaft,
NC(max) = NB(max)/cosα = NA/cos2α = 566.25 r.p.m.




4 - Question

A double universal joint is used to connect two shafts in the same plane. The intermediate shaft is inclined at an angle of 20° to the driving shaft as well as the driven shaft. Find the minimum speed of the driven shaft if the driving shaft has a constant speed of 500 r.p.m.
a) 532.1 r.p.m
b) 469.85 r.p.m.
c) 566.25 r.p.m.
d) 441.5 r.p.m.

View Answer

Answer: d
Explanation: Given α = 20° ; NA = 500 r.p.m.
Let A, B and C are the driving shaft, intermediate shaft and driven shaft respectively. We know that for the driving shaft (A) and intermediate shaft (B),
minimum speed of the driven shaft,
NC(min) = NB(min)× cos α = NAcos2α = 441.5 r.p.m.




5 - 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: In a pantograph, all the pairs are turning pairs. It has 4 links.




6 - 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) Both (a) and (b)

View Answer

Answer: d
Explanation: None.




7 - Question

Which of the following mechanism is used to enlarge or reduce the size of a drawing ?
a) Grasshopper mechanism
b) Watt mechanism
c) Pantograph
d) none of the mentioned

View Answer

Answer: c
Explanation: A 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.




8 - 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 Ackerman steering gear mechanism is much simpler than Davis gear. The difference between the Ackerman and Davis steering gears are :
1. The whole mechanism of the Ackerman steering gear is on back of the front wheels; whereas in Davis steering gear, it is in front of the wheels.
2. The Ackerman steering gear consists of turning pairs, whereas Davis steering gear consists of sliding members.




9 - Question

The driving and driven shafts connected by a Hooke’s joint will have equal speeds, if
a) cos θ = sin α
b) sinθ = ±√tanα
c) tanθ = ±√cosα
d) cot θ = cos α

View Answer

Answer: c
Explanation: None.




10 - Question

In a Davis steering gear, the distance between the pivots of the front axle is 1.2 metres and the wheel base is 2.7 metres. Find the inclination of the track arm to the longitudinal axis of the car, when it is moving along a straight path.
a) 12.5°
b) 13.5°
c) 14.5°
d) 15.5°

View Answer

Answer: a
Explanation: c = 1.2 m ; b = 2.7 m
Let α = Inclination of the track arm to the longitudinal axis.
We know that tan α = c/2b = 1.2/2 x 2.7
or, α = 12.5°.

Get weekly updates about new MCQs and other posts by joining 18000+ community of active learners