Pure rolling can be studied as a combination of translational motion and rotational motion about CM.
In the translational part: The velocity of each point of the wheel is same as the CM. So the lowermost point has a speed v rightwards.
In the rotational part, Each point on the rim has a velocity r directed along the tangent. So the lowermost point has a velocity r directed leftward (Assuming clockwise rotation)
So the net velocity of the lowermost point is the sum of the forward velocity v and the backward velocity r . If v = r then the net velocity of the point of contact is v - r = 0.
For the topmost point, the velocities due to translation and rotation are in the forward directions. So they add up to v + r. If v = r then topmost point moves with speed 2v.
Moderation Team
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r directed along the tangent. So the lowermost point has a velocity 
r directed leftward (Assuming clockwise rotation)
