Question

A water wave is generated in a ripple tank by an oscillator that vibrates 50 times in 30 seconds. A given trough of the wave travels 50.0 cm in 15 seconds. What is the wavelength of the water wave? Produce all your workings.

I got
50/30 = 1.67 vibrations per second = frequency

.5/15 = .033 waves per second = velocity

F(W) = V so W = V/F

But then my answers don't seem to be correct. Can someone please help out?
Thank you

Answer 1

T=30/50 = 0.6 s.
v=s/t= 0.5/15 = 0.033 m/s
λ=vT=0.033•0.6= 0.02 m

Answer 2

Frequency f = number of oscillations/times taken = 50/30s = 1.66Hz

Velocity of wave v = distance/time = 0.5m/15s = 0.033m/s

v = fλ

λ = v/f = 0.033/1.66 = 0.02