| A | B |
|---|
| sliding friction | friction that occurs when one solid surface slides over another |
| rolling friction | friction that occurs when an object rolls over a surface |
| fluid friction | friction that occurs as an object moves through a fluid |
| gravity | the force that pulls objects toward each other |
| free fall | the motion of a falling object when the only force acting on it is gravity |
| projectile | an object that is thrown |
| air resistance | the fluid friction experienced by objects falling through the air |
| terminal velocity | the maximum velocity a falling object can achieve |
| weight | a measure of the force of gravity on an object |
| momentum | the product of an object's mass and velocity |
| law of conservation of momentum | the rule that the total momentum of objects in an interaction does not change |
| Newton's third law of motion | this states that every time there is an action force on an object, the object will exert an equal and opposite reaction force |
| friction | the force that one surface exerts on another when the two rub against each other |
| satellite | any object that travels around another object in space |
| centripetal force | any force that causes an object to move in a circle |
