1. Unit 7 Waves & Beaches

2. Topic 2 Calculating Wave Properties
Wave terms:
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

3. Wave terms continued:
Wavelength – horizontal distance from crest to crest
Period – the time in seconds that it takes for one complete wave to pass 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.

4. Speed = wavelength / period
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?
v = 50 m/5 s
v = 10 m/s

5. More Wave Calculations
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?

6. More Wave Calculations
Frequency of a wave = 1wave / period
f = 1 wave/T
If a wave travels for 6 seconds, what is it’s frequency?

7. Calculations…
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 seconds.
What is the period?
What is the speed?
c. What is the frequency?