The Total solution for NCERT class 6-12
In each of thefollowing a force, F is acting on an object of mass, m. The direction ofdisplacement is from west to east shown by the longer arrow. Observe thediagrams carefully and state whether the work done by the force is negative,positive or zero.
Case I
In this case, the direction of force functioning on the block isperpendicular to the displacement. Therefore, work done by force on the blockare going to be zero.
Case II
In this case, the direction of force functioning on the block iswithin the direction of displacement. Therefore, work done by force on theblock are going to be positive.
Case III
In this case, the direction of force on the block is contrary tothe direction of displacement. Therefore, work done by force on the block aregoing to be negative.