Physics frequency question?
What length (in m) should an oboe have to produce a fundamental frequency of 305 Hz on a day when the speed of sound is 350 m/s? It is open at both ends.
What length (in m) should an oboe have to produce a fundamental frequency of 305 Hz on a day when the speed of sound is 350 m/s? It is open at both ends.
Andrew Smith
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An oboe is NOT open at both ends.
An oboe is a conical bore instrument like a saxophone.
It is ( almost) closed at the narrow dual reed mouthpiece and wide open at the bell.
So if you study "Bessel Horns" you discover that the modes of oscillation in a pure conical bore are at frequencies of 1,2,3,4,5,6 f0
But given that the wave is not reflected from a solid end what is f0?
OK so instead of an oboe how about we use a flute. Which IS open at both ends.
Therefore along the flute exactly 1/2 of a wave can fit. A positive maximum occurs at one end at the same moment that a negative maximum occurs at the other end.
So that for the total return distance exactly 1 wave fits.
ie the wavelength of the sound is v/f = 350/305 m
and the flute must be exactly half of this length.