Table Of Contents: What Is Work?
1. Definition of Work
Work occurs when a force is exerted on an object and causes the object to move. The force exerted and the movement of the object must be in the same direction to be considered work.
2. Work and Motion
If force is exerted and an object does not move, then work does not occur. For example, if you try to push a very heavy object, but the object does not move, then work is not done.
3. Work and Direction
If the force exerted is in a different direction than the movement of an object, then work does not occur. When you pick up a box, the exerted force and movement of the box are in the same direction, so work is done. However, when you carry a box, you are exerting force in a vertical direction to hold the box, but the box moves in a horizontal direction as you walk. Carrying the box is not considered work.
4. Calculating Work
The equation for work is force times distance. For example, if you use 5 Newtons of force to push a cart 10 meters, then the amount of work is equal to 50 Newton meters. If the cart becomes heavier and you need to exert 10 Newtons of force to move it the same distance, then the amount of work is equal to 100 Newton meters.
5. A Joule Is a Unit of Work
A Newton meter is also known as a joule. One joule is equal to the amount of work when one Newton is exerted to move an object one meter.