What is the frequency of a ship's whistle if the velocity of sound is 340 meters/second and the wavelength is 1.70 meters?

For any wave situation,

                       Frequency = (wavespeed) / (wavelength) .

 Frequency of the whistle = (340 meters per second) / (1.7meters) =

                                                   200 per second  =  200 Hz .

(1 Hz  =  1 per second)

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