| A | B |
|---|
| Acceleration | A change in velocity. |
| Action- Reaction Pair | For every action, there is an equal and opposite reaction. |
| Amplitude | The distance of a crest or trough from the rest postion (line of equilibrium). |
| Bouyant Force | A contact force exerted by a fluid on an object that is in a liquid. |
| Compound Machine | A machine made up of a combination of simple machines. |
| Compression | The part on a longitudinal wave where the spring is tight together. |
| Contact Fore | A friction force. |
| Crest | The top part of a transverse wave. |
| Diffract | The bending of a wave around a barrier. |
| Displacement | The distance between one point and another. |
| Efficiency | An object that does a good job at something and uses less energy. Ratio of output to input work. |
| Electromagnetic wave | It is the only wave that can travel without a medium. |
| Fluid | Liquid and gas. |
| Force | A push or a pull that changes the motion of an object. |
| Frame or reference or reference point | A stationary object used to determine if movement occured. |
| Frequency | The number of wavelenghts that pass a point in one second. |
| Friction | Force between two surfaces in contact that resists the movement of the surfaces as they pass eachother. |
| Gravity | The pull between all objects with mass. |
| Net force | The total force. |
| Velocity | Speed and direction combined. |
| Transverse Wave | The energy moves perpindicular to the vibrating matter. Matter in the medium moves at right angles in the direction of the waves movement. |
| Wavelength | The full distance betweem a crest and a trough. |
| Inclined plane | Also called a ramp, flat, low surface. |
| Input Force | The force that a person or a machine applies. |
| Output Force | The force exerted by the machine due to the input force |
| Joule | The SI unit for work. |
| Lever | Any rigid rod or plank that pivots or rotates around a point called a fulcrum. |
| Line of equilibrium | The resisting on a transverse wave. |
| Longitudinal wave | Also known as a compressional wave. |
| Lubricant | Material often petroleum or water based to reduce friction between objects. |
| Mechanical Advantage | The number of times the machine increases the input force. |
| Medium | A substance in which a wave can travel through. |
| Newton | The SI unit for force. |
| Newton's First Law | An object at rest will stay at rest and an object in motion will stay in motion until an outside force is acted upon it. |
| Newton's Second Law | The net force of an object is equal to the product of its acdeleration, or F= ma. |
| Newton's Third Law | For every action there is an equal and opposite reaction. |
| Inertia | The tendency of an object to resist changes in its velocity whether in motion or motionless. |
| Power | The rate at which work is done. Work divided by time. |
| Pulley | Consists of a grooved wheel with a rope or cable wrapped over it. |
| Rarefaction | The part of a compressional wave where the spring is spread out. |
| Reflect | Occurs when a wave strikes a surface and bounces off. |
| Refract | I a bending of a wave as it moves from one medium to another. |
| Screw | An inclined plane wrapped around a cylinder. |
| SI units | Unit of measurement is part of the international system of units. We often say " Metric System". |
| Simple Machine | A machine that does work with only one movement. |
| Trough | The bottom half of a transverse wave. |
| Vacuum | The volume of space that is emty of matter. |
| Virbration | Repeating back and forth motion. |
| Watt | Si units for power. |
| Wave | A disutbance that transfers energy from one place to another. |
| Wave Speed | Light travels faster than sound. Speed depends on the medium for mechanical waves. |
| Wedge | Inclined plane that can be moved. Often used to puch materials appart. |
| Wheel and Axle | Two circular objects of different diameters atrached sot theycan rotate together. |
| Work | When a force causes an object t move in the same direction that the force is applied. |
