Is it possible that a force is acting on a body but still work done is zero? Explain giving one example.

Yes, it the given condition is possible in certain conditions:-

(i) When Displacement is 0 or the initial point and final point are the same.


For e.g. When a car is moving on a road, there will be a frictional force applied by the road on the. Using Newton’s third law we can say that, for every action, there is an equal and opposite reaction. Thus the force applied by the road on the car will be equal and opposite to the force applied by the car on the road. Since, there is no displacement of the road, there will be no work done on the road.


(ii) When the Displacement is in perpendicular direction to force applied


For e.g. No work is done by the porter in carrying the load. As the porter carries the load by lifting it upwards and the moving forward it is obvious the angle between the force applied by the porter and the displacement is 90o (i.e., if Cos θ is zero or θ = π/2).


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