Question

define negative work.give two examples where negative work is done.

Answer 1

when force is acting opposite to the direction of displacement. eg when object is moved in straight direction the frictional force acts opposite to it

Answer 2

If the work done is in the direction opposite to the displacement of the body, it is known as negative work.

For e.g.- Work done by the Frictional force. (Which always acts opposite to the direction of displacement of the body)
               Work done by the buoyant force in a liquid acting on a sinking body.
               

Hope this helps..!! :)