What is the acceleration of a body revolving in a circle at uniform speed? the acceleration is zero. the acceleration is directed tangentially. the acceleration is directed toward the center. the acceleration is directed away from the center.

A body revolving in circle generally has tangential acceleration if the speed is changing. Since the speed is uniform here, the tangential acceleration is zero.

centripetal acceleration is directed towards the center and is given as

a = v²/r                    where a = centripetal acceleration , v = speed , r = radius

Since both speed and radius are constant here, the centripetal acceleration is constant and is always directed towards the center.

hence the correct choice is

The acceleration is directed toward the center.

you would expect a sound wave to speed up. - b)

coil wire, increase current, put iron inside the coil