Work done by force of static friction .

STATEEMNT-1 : Work done by frictional force is always either negative or zero. because STATEMENT-2 : Work done by the static friction on a system may be zero.

Work done by the force of friction

Why work done by force of friction is always zero ?

Assertion: Work done by the force of friction in moving a body around a closed loop is zero. Reason: Work done does not depend upon the nature of force.

Assertion: Work done by the force of friction in moving a body around a closed loop is zero. Reason: Work done does not depend upon the nature of force.

For a man walking on the floor, the force of friction between the floor and his feet accelerates him forword. What will be work done by the force of friction, postive, negative or zero?

Work done by static friction on an object :

Assertion: Static frictional force is a self adjusting force. Reason: Force of static friction does not depend upon the mass of the body.

Assertion: Static frictional force is a self adjusting force. Reason: Force of static friction does not depend upon the mass of the body.