At the highest point of a vertical circular track of radius

PHYSICS · Single correct · AP · Physics 1: Algebra-based · Force and Translational Dynamics · Force and Translational Dynamics

Problem

r

, what is the minimum speed an object must have to just maintain contact with the track? (Assume a uniform gravitational field of magnitude

g

.) (a)

g r

(b)

\sqrt{g r}

(c)

\sqrt{2 g r}

(d)

\sqrt{\dfrac{g}{r}}