| A | B |
|---|
| Work | The use of a force to move an object through a distance. |
| Simple machine | A device that makes a task easier by changing the size or direction of a force or the distance over which the force acts. |
| Lever | A bar that makes it easier to move things. |
| Fulcrum | The balance point on a lever that supports the arm but does not move. |
| Wheel-and -axle | A wheel with a rope that lets you change the direction in which you move an object. |
| Pulley | A wheel with a rope that lets you change the direction in which you move an object. |
| Inclined plane | A ramp or another sloping surface. |
| Balance forces | Forces that act on an object but cancel out other. |
| Unbalanced forces | Forces that act on an object and don't cancel out each other: unbalanced forces cause a change in motion. |
| Net force | The combination of all the forces acting on an object. |
| Bouyant force | The upward force exerted on an object by water. |
| Force | A push or pull that causes an object to move, stop,or change direction. |
| Friction | A force that opposes motion. |
| Gravity | The force of attraction between objects. |
| Gravitational force | The pull of all objects in the universe on one another. |
| Magnetic | Having the property of attracting iron objects |
| Magnetic force | The foirce produced by a magnet. |
