Water waves with a frequency of 4.5 Hz and a wavelength of 2.0m are traveling across a small harbor that is 200 m wide. How long does it take the waves to travel from one side of the harbor to the over?

22.2 seconds

Explanation:

recall that for a regular wave

v = fλ

where v = wave velocity (we need to find this to solve the next part)

f = frequency = 4.5 Hz

λ = wavelength = 2.0m

Substituting these into the equation above,

v = fλ

v = (4.5)(2)

v = 9.0m/s

Also recall that Distance travelled = velocity x time

in our case, we found velocity above (= 9.0 m/s) and the distance across the harbor is given as 200m, hence

Distance travelled = velocity x time

200 = 9.0 x time

time = 200/9.0

time = 22.2 seconds

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