Question

Which is the false statement about the properties of instantaneous centre?

(a) at the instantaneous centre of rotation, one rigid link rotates instantaneously relative to another for the configuration of mechanism considered

(b) the two rigid links have no linear velocities relative to each other at the instantaneous centre

(c) the two rigid links which have no linear velocity relative to each other at this centre have the same linear velocity to the third rigid link

(d) the double centre can be denoted either by O21 or O12, but proper selection should be made

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The above asked question is from Properties of Instantaneous Centre topic in portion Velocity in Mechanisms of Machine Kinematics

Answer 1

Right option is (d) the double centre can be denoted either by O21 or O12, but proper selection should be made

The best explanation: The following properties of the instantaneous centre are important from the subject point of view :

1. A rigid link rotates instantaneously relative to another link at the instantaneous centre for the configuration of the mechanism considered.

2. The two rigid links have no linear velocity relative to each other at the instantaneous centre. At this point (i.e. instantaneous centre), the two rigid links have the same linear velocity relative to the third rigid link. In other words, the velocity of the instantaneous centre relative to any third rigid link will be same whether the instantaneous centre is regarded as a point on the first rigid link or on the second rigid link.