A circular disk (wheel) of radius r rolls in its plane along a general convex curve of

varying radius of curvature R such that all motion is

confined to a single vertical plane. The contact point O'

traverses the curve at a constant speed of v0. (a) Find

the absolute velocity of the point P on the rim. (b) Find

the absolute acceleration of the point P on the rim.

Express the results in terms of the unit vectors e_n and e_t.