Wave vocabulary and formulas
 Wave terms:
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Still water level – water level when the surface is flat and smooth with no waves
Crest – the highest point of a wave
Trough – the lowest point of a wave below the still water mark.
Amplitude – distance from rest to crest or rest to trough
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Wavelength – horizontal distance from crest to crest
Wave height-distance from crest to trough
Period – the time in seconds that it takes for one complete wave to pass through a fixed point.
Frequency – the # of wave crests that pass a fixed point per unit of time
Wave speed – The speed of the wave in a certain direction expressed as distance per unit of time.
Wave Calculations
 We can calculate the speed (v) of a wave from its wavelength (λ) and period (T).
Speed = wavelength / period
v=λ/T
If a wave takes 5 seconds to have a wavelength of 50 meters, what is the speed of the wave?
 If a waves travels at 4 m/s and travels for 30 seconds, what is it’s wavelength?
 How long would it take if a wave travels at a speed of 6 m/s for 120 m?
Frequency of a wave = 1wave / period
f = 1 wave/T
 If a wave travels for 6 seconds, what is it’s frequency?
 When the crest of wave A passed point P, the watch read 0.00 seconds. When the crest of wave B passed point
P, the watch read 10.00 seconds. The wavelength is 15m.
a. What is the period?
b. What is the speed?
c. What is the frequency?