The wave takes 11.3 s to cover a distance of 26.5 m, so its speed is:
[tex]v= \frac{S}{t}= \frac{26.5 m}{11.3 s}=2.35 m/s [/tex]
The distance between two consecutive crests is 3 m, and this corresponds to the wavelength of the wave. To find its frequency, we can use the relationship between the speed v, the wavelength [tex]\lambda[/tex] and the frequency f:
[tex]f= \frac{v}{\lambda}= \frac{2.35 m/s}{3 m}=0.78 Hz [/tex]
