Question

A wave of frequency 400hz in air has a speed of 320m/s find its wave length. what will be the new wave length when it enters water in which its speed is 1600m/s​

Answer 1

There is a formula: λ = v/f , where λ is wavelength, v is velocity, and f is frequency.

On substituting the given values,

λ = 320/400

λ = 0.8 m

Now for the second part we use the same formula.

Hence, λ = 1600/400  (Frequency of waves will be constant even if medium changes)

λ = 4 m