2 relationships for waves

1) speed and frequency = directly proportional
(as speed goes up, frequency goes up)
2) wavelength and frequency = inversely proportional
(as wavelength gets longer, frequency goes down)


for transverse waves: the distance between the resting point (or equilibrium) to the crest or trough

constructive interference

when waves combine to a larger amplitude


highest point (peak) of a wave

destructive interference

when waves cancel each other out


the spreading out of waves through an opening or around the edges of an obstacle

diffraction examples

light will bend around a lampshade; sounds can be heard even if you are hiding behind something

EM Wave

electromagnetic wave; moves energy through space (sometimes empty space, sometimes through a medium)

Examples of EM Waves

Radio, infrared (IR), light

Examples of mechanical waves

Sound, ocean waves, earthquakes


the number of waves passing a fixed point in a certain amount of time; it is based partly on wavelength (longer wavelengths take a longer time to pass) and partly on the speed the wave travels


the meeting and combining of waves

mechanical wave

waves that transfer energy through matter


any substance that a wave moves through


the bouncing back of a wave as it strikes a barrier

reflection examples

mirror (light waves), echo (sound waves), RADAR (radio waves)


the bending of a wave as it enters a new medium at an angle other than 90 degrees

refraction examples

a straw looks "broken" when you look at it in a glass of water (because the light bends when it enters the water)


lowest point (valley) of a wave


a disturbance that transfers energy from one place to another


the distance from one wave crest to the very next crest. (This may also be measured from trough to trough.)

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