The wavelength is 4 m, and the velocity of its propagation is 20 m / s. With what frequency does the wave source oscillate?

There is a formula for wave propagation:
υ = λ * ν,
Where
υ is the wave speed;
λ is the wavelength;
ν is the frequency of the wave.
Let us express the frequency ν:
ν = υ / λ
ν = 20/4 = 5 (Hz).
Answer: ν = 5 Hz



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