When a body moves on an inclined plane with constant velocity, the work done on the body is zero. This is because work is defined as the product of force and displacement, and when the velocity is constant, there is no acceleration and thus no net force acting on the body.
In this scenario, the force of gravity acting on the body is partially counteracted by an equal and opposite normal force exerted by the inclined plane. The component of the force of gravity parallel to the inclined plane, known as the gravitational force component along the incline, is balanced by the static or kinetic friction force, depending on whether the body is at rest or in motion. This friction force ensures that the body maintains a constant velocity despite the opposing gravitational force.
Since the friction force is acting in the opposite direction to the displacement of the body, the work done by the friction force is negative. However, the work done by the gravitational force component along the incline is positive. These two work contributions cancel each other out, resulting in a net work done of zero.
Therefore, when a body moves on an inclined plane with constant velocity, the work done on the body is zero. This implies that no energy is being transferred to or from the body, as the work-energy theorem states that the work done on an object is equal to the change in its kinetic energy.