| A | B |
|---|
| Force | a push or a pull that acts on an object |
| Newton | SI unit for force, equal to the force that causes a 1kg mass to accelerate a a rate of 1 meter per second squared |
| Net Force | the overall force acting on an object after all the forces are combined |
| friction | a force that opposes the motion of objects that touch as they move past each other. |
| static Friction | a friction force that acts on objects that are not moving |
| sliding friction | a friction force that opposes the motion of an object as it slides over a surface |
| rolling friction | a friction force that acts on rolling objects, caused by the change in shape at the point of rolling contact |
| Fluid friction | a friction force that opposes the motion of an object through a fluid |
| air resistance | fluid friction acting on an object moving through the air |
| gravity | the attraction between any two objects because of their masses |
| terminal velocity | the constant velocity of a falling object when the force of air resistance equals the force of gravity |
| projectile motion | the curved path of an object in free fall after it is given an initial forward velocity |
| interia | the tendency of an object to resit a change in its motion |
| mass | the amoutn of matter in an object; a measure of the inertia of an object, which depends on the amount of matter the object contains |
| weight | the force of gravity acting on an object |
| momentum | the product of an object's mass and its velocity |
| law of conservation of momentum | law stating that the total momentum of a system does not change if no net force acts on the system |
| gravitational force | an attractive force that acts between any two objects |
| centripetal force | a force that continuously changes the direction of an object to make it move in a circle |
