Question

A wave hits the beach about every 2.0 seconds on a calm day. If it crests are 5.00 meters away from each other, what is the speed of the wave

Answer 1

2.5 m/s

Step-by-step explanation:

The speed of a wave is given by:

`v=f\lambda`

where

f is the frequency

`\lambda` is the wavelength

The wave in this problem hits the beach about every 2.0 seconds: this means that its period is 2.0 s. So the frequency is the reciprocal of the period

`f=(1)/(2.0 s)=0.5 Hz`

The crests are 5.0 m away from each other, so the wavelength is

`\lambda=5.0 m`

Therefore, the speed of the wave is

`v=(0.5 Hz)(5.0 m)=2.5 m/s`