Question

If the force and the displacement are in the opposite direction, then negative work is done on the object; the object subsequently loses mechanical energy.

a. true
b.false

Answer 1

If the force and displacement are in the opposite direction, positive work is done on the object and the object gains mechanical energy.

Step-by-step explanation:

The statement given in the question is incorrect. If the force and the displacement are in the opposite direction, then positive work is done on the object, and the object gains mechanical energy, not loses it.

This can be understood by considering the definition of work: work is done when a force is applied to an object and the object moves in the direction of the force. If the force and displacement have opposite directions, the work done is negative. However, the change in kinetic energy of an object is given by the work done on it, so if negative work is done, the object actually gains kinetic energy and therefore mechanical energy.

For example, if you push a box against the force of friction, your force is in the opposite direction of the displacement, but the box gains mechanical energy as it moves.