| A | B |
|---|
| Acceleration | rate of change in velocity |
| Force | a push or pull that gives energy to an object, sometimes causing a change in the motion of the object |
| frame of reference | background or point that is assumed to be stationary and is used for comparison when motion is described |
| fulcrum | fixed pivot point of a lever |
| inclined plane | straight slanted surface that multiplies force |
| joule | unit of work and energy; 1 newton-meter |
| lever | a rigid bar free to move about a single point; there may be first- class, second class, or third class depending on the position of the effort force, resistance force, and fulcrum |
| machine | a device that makes work easier by changing the amount and direction of force or by changing the direction of force |
| motion | a change in position in a certain amount of time |
| newton | unit of force; 1kg x 1m/sec/sec |
| pulley | rope, belt or chain wrapped around a wheel ; can either change the amount of force or the direction of force |
| screw | inclined plane wrapped around a central bar to form a spiral |
| speed | rate at which an object moves |
| velocity | description of speed in a given direction |
| wedge | an incline plane that moves |
| wheel and axle | a machine made up of two circular objects of different sizes; a force is applied to the wheel and transferred to the axle |
| work | force acting over a distance to move an object |
