A ball is whirled on the end of a string in a horizontal circle at constant speed. Suddenly, the string breaks. Immediately after the string breaks, the ball will
A) have a horizontal velocity away from the center of the circle.
B) have a horizontal velocity that is tangential to the circle.
C) have a horizontal velocity toward the center of the circle.
D) have a horizontal velocity partly in away from the center of the circle and partly tangent to the circle.
E) have no horizontal velocity.

Question

Quizplus · Accepted Answer

When the string breaks, the only force acting on the ball is its own inertia, which causes it to continue moving in a straight line tangent to the circle. Therefore, the ball will have a horizontal velocity that is tangential to the circle.

A Ball Is Whirled on the End of a String