Pitch of an Organ Pipe

We want to know the pitch of an organ pipe. The pitch is measured as a frequency v with the physical dimension of. We know intuitively that the pitch is somehow dependent on the length / of the flue pipe. 

To be correct in dimensions, there must be also a velocity in the equation. Therefore, we set up the relationship as 

We interpret the velocity v as the velocity of sound, k is dimensionless function, turning out to be 0.5 for an open flue pipe, i.e., half of the wavelength. Even Lord Rayleigh was engaged in the pitch of organ pipes [30]. 

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