When a force is applied to an object horizontally and it moves, what contributes to the net work done?

In the context of this question, the net work done on an object when it is moved by an applied force horizontally considers both the force that is applied and the opposing forces, such as friction. The net work is calculated by taking into account the effective force that contributes to the motion of the object, which is determined by the difference between the applied force and friction.

When a force is applied to an object, this force tends to move the object in the direction of the applied force. However, if there is friction acting against the movement, it reduces the effective force that causes the object to accelerate. Therefore, the net work done on the object is the result of the applied force minus the opposing frictional force. This net force, when multiplied by the distance moved, gives the total work done in the direction of the applied force.

In summary, the rationale for why the difference between the applied force and friction contributes to the net work done is rooted in Newton's second law, which emphasizes that the net force acting on an object dictates its acceleration and hence the work done.