The figure shows a top view of a ball on the end of a string traveling counterclockwise in a circular path.Assume that air resistance is negligible.The free-body diagram that best represents the acceleration of the ball is
A)1
B)2
C)3
D)4

Question

The figure shows a top view of a ball on the end of a string traveling counterclockwise in a circular path.Assume that air resistance is negligible.The free-body diagram that best represents the acceleration of the ball is 
A)1 
B)2 
C)3 
D)4

Quizplus · Accepted Answer

The acceleration of the ball is directed towards the center of the circular path, which is represented by the vector labeled "C" in diagram 4. The weight of the ball is directed downward, and the tension in the string is directed towards the center of the circular path, so these forces cancel out in the horizontal direction. Therefore, there is no horizontal component of acceleration, and the correct free-body diagram must show a net force acting only in the vertical direction, which is represented by diagram 4.

The Figure Shows a Top View of a Ball on the End