Question

define three types of work

Answer 1

positive work done - when force is applied in direction of displacement and displacement is there .

negative work done - when force is applied in opposite direction to the displacement and displacement will be negative .

zero work done - when no displacement is done but force is applied .

Answer 2

There are three types of work:
1) Positive work
-This occurs when the displacement occurs in the direction of the force applied.
-eg., When a body falls freely under gravity, the work done by the gravitational force is positive.
2)Negative work
- This occurs when the displacement occurs in the opposite direction of the force applied
-eg., the work done by the frictional force when a body is moving.
3)Zero work
-Work done is zero if the force applied has the magnitude zero or the displacement of the body is zero.
-eg., a man pushing a wall which does not move.