What is meant by positive work, negative work and zero work? Give one example of each.

Explanation

Positive work: If a force acting on a body has a component in a direction of the displacement.
Eg: When a body falls under free fall. `(theta=0^(@))`
Negative work: If a force acting on a body has a component in the opposite direction of the displacement.
Eg: When brakes are applied to a moving vehicle, the work done by the brake force is negative.
Zero work: If the body gets displaced along a direction perpendicular to the direction of applied force.
Eg: When a coolie walks on a horizontal platform with load.