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ashley89
To determine a waves' frequency, you must know the
velocity of wave and wavelength velocity=wavelength*frequency i.e V=L*f f=V/L
For reference:\[\large f = freq, v = velocity, \lambda = wavelength, p = period, T = time\] The wave equation is defined as:\[\large v=\frac{\lambda}{p}\]Knowing that period is defined as:\[\large p=\frac{1}{f}\]You can rewrite the wave equation as as:\[\large v=\lambda f\]Rearrange that to see that:\[\large f=\frac{v}{\lambda}\]So you need to know the wavelength and the velocity to determine a wave's frequency.