Question

A stone tied to a string is rotated in a circle. If the string is cut, the stone flies away from the circle because:
A. A centrifugal force acts on the stone
B. A centripetal force acts on the stone
C. Of its inertia
D. Reaction of the centripetal force

Answer 1

Hint: In this question we will apply the concept of centripetal force, check various forces on the stone when it is tied to the string and forces after the string is cut.

Complete step by step solution:
When the stone is tied to a string centripetal force is in action which is responsible for its circular motion but when the string is cut, the centripetal force due to the string is no longer in action. Therefore option (A) is incorrect.

Centrifugal force and centripetal force are action and reaction forces in nature, when there is no longer centripetal force and centrifugal force will also become zero(no action so no reaction) therefore option (B) is also incorrect.

And reaction of centripetal force is centrifugal force so this option also cannot be the answer therefore option (D) is also incorrect.

So, due to its inertia of motion it continues in the tangential direction. Inertia is the ability of the body to maintain its state whether it is state of rest or state of motion, the role massplays in translational motion is played by inertia in rotational motion.

Therefore the correct answer is option C.

Note: Make sure that the centripetal force will act only for the time when stone is tied to the string. No string, no centripetal force. Moreover, centripetal force is the component of force applied on an object in curvilinear motion that is directed towards the axis of rotation or the centre of curvature.