## Sounds Of Music C

SciolyMaster
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### Re: Sounds Of Music C

smayya337 wrote:
SciolyMaster wrote:
smayya337 wrote: Close, but not quite! Your numbers were all off by the same factor - you might want to check your math again.
Isn't it a closed air column though? The wavelength should be 4x the length of the room,
$343/(4*50)=1.7$for the two 50 m sides and $343/(4*20)=4.3$for the 20 m side.
From what I understand, the formula for a closed rectangular box's resonant frequencies should be $\frac{v}{2} = \sqrt{(\frac{l}{L_x})^2+(\frac{m}{L_y})^2+(\frac{n}{L_z})^2}$, and with $L_x = 50, L_y = 50$, and $L_z = 20$, you can substitute 0, 0, and 1 in any order as $l, m,$ and $n$ to get [b]3.4 Hz and 8.6 Hz[/b].

The simpler way, of course, would also be to just find $343/(2*50)$ and $343/(2*20)$

I think you got a fully closed air column confused with a stopped air column, which is closed on one side but not the other. To the best of my knowledge, a fully closed air column should have a fundamental wavelength 2x the length of the room, similar to a string.
Yeah you're right, I used the equation for an air column closed on one side only.