Question

A stone tied to a string is whirled in a circle. As it is revolving, the rope suddenly breaks. Then :
A) The stone flies off tangentially.
B) The stone moves off radially.
C) The stone moves radially outward.
D) The motion of the stone depends upon its velocity.

Answer 1

A body moving in a circle experiences two kinds of force one is centrifugal force and other is tangential force. The centrifugal force keeps the body in the circular track and the tangential force keeps the moving in the circular track.

Complete step by step answer:
It is given that a stone is tied to a string with a rope and whirled in a circle and at any moment the rope breaks and we need to tell in which direction the stone flies after the rope breaks. The body under the circular motion experiences a centrifugal force and a tangential force. The centrifugal force keeps the body to continuously be in a circular track and the tangential force acts in the direction tangent to the circular track. Among the centrifugal and tangential force the tangential force is responsible for the movement of the body. The force of the centrifugal is represented by the tension in the rope and as the rope breaks the centrifugal force no longer acts on the stone only the tangential force will be working and that too for some time. So when the rope suddenly breaks due to acting of the tangential force and absence of the centrifugal force the stone flies off tangentially.

The option A is correct.

Note: The body that is tied to a rope is moving in a circular track. The rope breaks only if the tension in the string increases then the permissible strength of the rope and the rope no longer can withstand the tension.