Question

Is it possible to do work on an object without changing the kinetic energy of the object?

Answer 1

answer) the answer is yes it is possible.

the kinetic energy will only change if we change the velocity of the object, for example if we move an object on a rough surface at a constant velocity it means we are applying an external force to keep this velocity constant,  then two things are happening, we are doing positive work on the object and the opposing force, which is force of friction is doing negative work , so we can see that the work is being done on the object by the external force and frictional force while the kinetic energy is the same.

from work energy energy theorem we have

Work done by conservative forces+ work done by non conservative forces+work done by external forces=change in kinetic energy...................1)

conservative forces=gravitational force, electrostatic force etc

non conservative force=frictional force, drag force etc

so here we see conservative force=0 since velocity is constant and also kinetic energy is zero but we have from eqn 1)

work done friction=work done by external forces.