| A | B |
|---|
| force | a push or pull |
| net force | all forces are added together |
| unbalanced forces | when a net force is acting on an object -causes the change motion |
| balanced forces | forces acting on one object in opposite directions-will not cause an object to move or change motion |
| inertia | tendency of an object to resist change |
| mass | amount of matter in an object |
| sliding friction | two solid objects slining over each other |
| rolling friction | when an object rolls over another object |
| fluid friction | when an object moves through a liquid or a gas |
| friction | the force that one surface exerts on another |
| gravity | force that pulls objects toward each other |
| free fall | when the only force acting on an falling object is gravity |
| projectile | an object that is thrown |
| air resisatance | fluid friction from the air when an object is falling |
| weight | measure of the force of gravity on an object |
