Number of Degrees of Freedom for Plane Mechanisms

Question 1
Marks : +2 | -2
Pass Ratio : 100%
When two links are connected by a pin joint, their instantaneous centre lies
on their point of contact
at the centre of curvature
at the centre of circle
at the pin joint
Explanation:
None.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
The total number of instantaneous centres for a mechanism consisting of n links are
n/2
n
n-1
n(n-1)/2
Explanation:
The number of pairs of links or the number of instantaneous centres is the number of combinations of n links taken two at a time. Mathematically, number of instantaneous centres, n(n-1)/2.
Question 3
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Pass Ratio : 100%
In a mechanism, the fixed instantaneous centres are those centres which
remain in the same place for all configurations of the mechanism
vary with the configuration of the mechanism
moves as the mechanism moves, but joints are of permanent nature
none of the mentioned
Explanation:
Fixed instantaneous centres remain in the same place for all configurations of the mechanism.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
When a slider moves on a fixed link having ____________ their instantaneous center lies at infinity.
straight surface
curved surface
oval surface
none of the mentioned
Explanation:
When a slider moves on a fixed link having curved surface, their instantaneous centre lies at the centre of curvature.
Question 5
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The instantaneous centres, which moves as the mechanism moves but joints are of permanent nature, are called permanent instantaneous centres.
True
False
Explanation:
The permanent instantaneous centres move when the mechanism moves, but the joints are of permanent nature.
Question 6
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The magnitude of velocities of the points on a rigid link is
directly proportional to the distance from the points to the instantaneous centre and is parallel to the line joining the point to the instantaneous centre.
directly proportional to the distance from the points to the instantaneous centre and is perpendicular to the line joining the point to the instantaneous centre.
inversely proportional to the distance from the points to the instantaneous centre and is parallel to the line joining the point to the instantaneous centre.
inversely proportional to the distance from the points to the instantaneous centre and is perpendicular to the line joining the point to the instantaneous centre.
Explanation:
None.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
The instantaneous centres which vary with the configuration of mechanism, are called
permanent instantaneous centres
fixed instantaneous centres
neither fixed nor permanent instantaneous centres
none of the mentioned
Explanation:
Neither fixed nor permanent instantaneous centres vary with the configuration of the mechanism.
Question 8
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Pass Ratio : 100%
Which of the following property of the instantaneous center is correct?
A rigid link rotates instantaneously relative to another link at the instantaneous centre for the configuration of the mechanism considered.
The two rigid links have no linear velocity relative to each other at the instantaneous centre.
The velocity of the instantaneous centre relative to any third link is same whether the instantaneous centre is regarded as a point on the first link or on the second rigid link.
all of the mentioned
Explanation:
None.
Question 9
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Pass Ratio : 100%
According to Kennedy’s theorem, if three bodies move relatively to each other, their instantaneous centres will lie on
straight line
parabolic curve
triangle
rectangle
Explanation:
The Aronhold Kennedy’s theorem states that if three bodies move relatively to each other,
Question 10
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Pass Ratio : 100%
The two links are said to have a pure rolling contact, when their instantaneous centre __________ on their point of contact.
lies
does not lie
Explanation:
None