Centrifugal Reaction - QS Study

Centrifugal reaction:

Centripetal force acting on the body rotating in a circular path is applied from outside. The body which applies this outside force, according to Newton’s third law of motion equal and opposite force is applied on that body by the first body. Obviously, this reaction force acts along the radius vector towards outside. This is called centrifugal reaction.

Suppose by fastening a piece of stone with a thread is rotated in a circular path [Figure]. All the time a centripetal force FC is acting on the stone by the thread. Here tension of the thread is the necessary centripetal force. If the thread is turn off, then action of the centripetal force stops; instantaneously the stone swiftly moves away along the tangent of the circle with uniform speed in a straight line. While rotating the stone by the hand in a circular path, the stone also applies equal and opposite reaction FR on the hand; as a result, the hand feels a tension outward.

Like other action – reaction here also FC and FR do not act on the same body, but act on two different bodies, for example, respectively on the stone and on the hand. When the thread tears off then two forces disappear simultaneously.

Many other examples may be cited on centripetal force. Each planet in the universe revolves round the sun. The gravitational attraction force that the sun applies on those planets, acts as centripetal force on the planets.