Assertion: In a circular motion,work done by | vedclass

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(D) In uniform circular motion,the centripetal force is always perpendicular to the velocity vector,so the work done by it is zero. However,the assert

Vedclass · Accepted Answer

Assertion is false and Reason is true.

Vedclass · Answer

(D) In uniform circular motion,the centripetal force is always perpendicular to the velocity vector,so the work done by it is zero. However,the assertion states 'In a circular motion,work done by centripetal force is not always zero'. This is false because the centripetal force is defined as the component of the net force directed towards the centre,which is always perpendicular to the instantaneous displacement. Thus,the work done by centripetal force is always zero in any circular motion.The reason states that if the speed changes,the net force is not towards the centre. This is true because,in non-uniform circular motion,there is a tangential acceleration component,meaning the net force has both radial (centripetal) and tangential components. Therefore,the net force is not directed towards the centre. Since the Assertion is false and the Reason is true,the correct option is $D$.

Assertion: In a circular motion,work done by centripetal force is not always zero.
Reason: If the speed of the particle increases or decreases in circular motion,then the net force acting on the particle does not remain towards the centre.

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Assertion: In a circular motion,work done by centripetal force is not always zero.Reason: If the speed of the particle increases or decreases in circular motion,then the net force acting on the particle does not remain towards the centre.