click below
click below
Normal Size Small Size show me how
Forces
| Term | Definition |
|---|---|
| force | a push or pull that causes a change in motion |
| applied force | a physical push or pull between two objects or people |
| friction | the force that opposes motion and causes objects to slow down |
| gravity | attractive force between any two objects that cause mass |
| air pressure | forces applied by a moving gas |
| electromagnetic force | the force between charged objects |
| centripetal force | force that makes objects spin or change direction |
| buoyancy | fluid force on objects to make them float |
| lift | upward force of air that causes objects to rise when moving at a high rate of speed (airplanes and helicopters) |
| magnitude | the strength of a force |
| Newtons | the unit for force |
| vector | an arrow used in a free-body diagram and tells you the magnitude and direction of a force |
| net force | the total or resulting force acting on an object |
| normal force | the support force caused by a surface against an object |
| Newton's First Law of Motion | an object stays in motion or stays at rest unless acted on by an unbalanced force |
| Newton's Second Law of Motion | the mass of an object is directly proportional to the force applied on it and inversely proportional to its acceleration (F=ma) |
| Newton's Third Law of Motion | every action has an equal but opposite reaction |
| inertia | an object's resistance to changing its motion |
| acceleration due to gravity | the rate at which objects accelerate toward the Earth when the force of gravity pulls on them (9.8 m/s2) |
| weight | the force produced by an object's mass due to gravity (Fw=mg) |
| mass | how much matter is in an object |
| static friction | when two objects are touching each other but the force of friction is preventing movement |
| air friction (drag) | the force that slows down an object when it is falling and cutting through the air |
| sliding friction | when two objects are moving past each other but with some resistance |
| viscous friction | friction created by a liquid running over a surface |
| rolling friction | created by one object rolling over another |
| momentum | mass in motion and how hard it is to make an object stop |