| A | B |
|---|
| gravity | a force that pulls any two object together, such as you and the earth |
| work | the result of a force moving an object |
| energy | the ability to do work |
| kinetic energy | energy of motion |
| potential energy | stored energy |
| mechanical energy | the energy an object gets from its motion |
| chemical energy | energy that results from chemical changes |
| simple machine | a machine made of only one or two parts |
| efficiency | the amount of work a machine does compare to the amount of energy put into using the machine |
| compound machine | a machine made of two or more simple machines |
| complex machine | a machine made of many simple and coumpound machines |
| inertia | the tendency of a moving object to stay in motion or resting object to stay still |
| friction | a froce that slows the motion of moving objects |
