Centripetal Acceleration

The circular disc of radius rolls without slipping. Its centre of mass is and is point
where body is in contact with the surface at any instant. At this instant, each particle of body is moving at right angles to the line which joins the particle with point with velocity
proportional to distance. In other words the combined translational and rotational motion
is equal to pure rotation and body moves constant in magnitude as well as direction.

According to the question, we can draw the following diagram

From the diagram

and
Now,