| A | B |
|---|
| Linear Motion | motion that goes from one place to another without repeating |
| Harmonic Motion | motion that repeats in cycles |
| Cycle | a unit of motion that repeats |
| Pendulum | a device that swings back and fourth due to the force of gravity |
| Oscillator | a physical system that has repeating cycles |
| Restoring Force | Any force that always acts to pull a system back toward equilibrium |
| Period | the time it takes for each complete cycle |
| Frequency | how often something repeats, expressed in hertz |
| Hertz | the unit of frequency, one hertz is one cycle per second |
| Amplitude | the amount that a cycle moves away from equilibrium |
| Natural Frequency | the frequency at which a system oscillates when disturbed |
| Periodic Force | a repetitive force |
| Resonance | an exceptionally large amplitude that develops when a periodic force is applied at the natural frequency |
| Wave | a traveling oscillation that has properties of frequency, wavelength, and amplitude |
| Wavelength | the distance from any point on a wave to the same point on the next cycle of the wave |
| Transverse | a wave is transverse if its oscillations are not in the direction it moves |
| Longitudinal | a wave is longitudinal if its oscillations are in the direction it moves |
| Constructive Interference | when waves add up to make a larger amplitude |
| Destructive Interference | when waves add up to make a smaller, or zero, amplitude |
| Pitch | the perception of high or low that you hear at different frequencies of sound |
| Decibel | measure of the loudness (amplitude) of sound |
| Supersonic | faster than the speed of sound |
| Doppler Effect | an increase or decrease in frequency caused by the motion of a source of sound |
| Equilibrium | state in which the net force on an object is zero |
| Refraction | the wave bends as it passes into and through an object |
| Reflection | the wave bounces and goes in a new direction |
| Diffraction | the wave bends around an object or through holes in the object |
| Absorption | the wave is absorbed and disappears |
| Law of Inertia | when the net force is zero, objects at rest stay at rest and objects in motion keep moving with the same speed and direction |
| Inertia | the property of an object that resists changes in its motion |
| Newton's 2nd Law | acceleration is force divided by mass |
| Newton's 3rd Law | for every action force there is a reaction force equal in strength and opposite in direction |
