Final answer:
Work occurs when a force is applied on an object and there is displacement in the direction of the force. Both force and displacement are necessary for work to be done.
Step-by-step explanation:
Work, in the scientific sense, is defined as the product of the force applied on an object and the displacement of that object in the direction of the force. It is essential that both force and displacement occur for work to be done. For example, if you push a box across a room, the force you apply and the distance the box moves in the direction of the force are both necessary for work to be done. However, if you push the box without any displacement, no work is being done.