Question

when you whirl a can overhead by a string in a circular path, what is the direction of the force exerted on the can?
radially outward from the center of the circle.
tangent to the circle in the direction of motion of the can.
tangent to the circle and opposite in direction to the motion of the can.
toward the center of the circle.

Explanation:

When an object moves in a circular path, a centripetal force acts on it. The centripetal force always points towards the center of the circle. In the case of the can whirled by a string in a circular path, the tension in the string provides the centripetal force which is directed towards the center of the circular path.

Answer:

Toward the center of the circle.