Question

A body is rotating nonuniformly about a vertical axis fixed in an inertial frame. The resultant force on a particle of the body not on the axis is.

(a) vertical

(b) horizontal and skew with the axis

(c) horizontal and intersecting the axis

(d) none of these.

Answer 1

(b) horizontal and skew with the axis

Explanation: 

Since the body is rotating nonuniformly about a vertical axis, a particle not on the axis will move on a circular path in a horizontal plane. It will have both radial and tangential accelerations and hence radial and tangential forces. The resultant force of these two mutually perpendicular forces will be in the horizontal plane but will not cross the axis.