A disc is performing pure rolling on a smooth stationary surface with constant angular velocity as shown in figure. At any instant, for the lower most point of the disc -

Step-by-step solution

As the disc is in combined rotation and translation, each point has a tangential velocity and a linear velocity in the forward direction. From figure v _ net (for lowest point) = v - R = v - v =0 and acceleration = v ² R +0= v ² R (since linear speed is constant)