| A | B |
|---|
| third | which of Newton's law says for every action there's an opposite an equal reaction |
| Newton | physicist known for his three laws of physics |
| balloon | the most important part of a reaction rocket balloon racecar's motor |
| axles | the bars that hold the wheels |
| force | a push or pull that transfers energy to an object |
| drag | the force of friction on an object |
| friction | a force that opposes motion and brings an object to rest |
| gravity | the force that pulls objects toward the center of the Earth |
| thrust | the force that propels vehicles forward |
| applied physics | the study of the ways in which objects are moved and work is done |
| inertia | the tendency of an object to remain still or to continue to move in the same straight line unless some outside force acts upon it |
| machine | a device designed to obtain the greatest amount of force from the energy used |
| mechanical advantage | the increase in force gained by using a machine |
| power | the rate at which work is done |
| work | the application of force to cause an object to move in the direction of the force |
| motion | an object's movement and the study which involves force, friction, and gravity |
| vehicles | cars, trains, planes, rockets, skateboards, boats are all ______________________ |
