This applet shows the **positon**,**velocity **and **acceleration****vectors**
of a point on the rim of a body **rolling without slipping**on a stationary surface.
1. The term freely rolling means that there is no slipping (v=rw) at the point of contact with the ground--no skidding (v>rw) and no spinning in place (w>v/r),where v,r and w are the linear speed, radius andthe angular speed of the rolling body.

2. The center of the wheel has a linear speed (with respect to ground) equal to that of any point on its rim (with respect to center).

3. For circular motion (in the reference framemoving with the velocity of the center of the rolling body) :

The acceleration **a** of a point always points in a directionopposite the position vector **r**,

and the velocity vector **V** is perpendicular to both of them.

4. Observe the velocity vectors of a point on the rimof the rolling body.

The white vector represents the velocity of the centerwith resepect to ground and

the red vector represents the velocity of the pointwith respect to the center.

The sum of these two vectors is the cyan vectorrepresenting velocity of the point relative to ground.

5. The green curve shows the trajectory of a point on the rim.