Can Two Speakers Produce Destructive Interference with Longitudinal Waves?

AI Thread Summary
Destructive interference between two speakers producing longitudinal waves can occur at specific distances, but the conditions depend on their phase and direction. The problem involves two speakers 3.20m apart emitting a 214Hz tone, and the speed of sound is 343 m/s. The confusion arises regarding the use of m=0 for calculating the shortest distance for destructive interference, as it typically applies to the formula m + (1/2) for destructive interference. One participant questions whether true cancellation can occur in front of one speaker due to the directional nature of longitudinal waves. The discussion highlights the complexities of wave interference and the need for clarity on wave behavior in different contexts.
Gentec
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Good day

I have tried the following problem a few times and come up with ansers larger than 3.20m.

The problem: Two speakers are 3.20m apart and facing the same direction and are in phase. They each produce a 214Hz tone. What is the shortest distance directly in front of one speaker where there would be destructive interference? S of Sound is 343 m/s

Am I correct in using m=0?

Thanks for your time
 
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destructive interference between two waves occurs at m+(1/2) where m=0,1,2,3,...

so, m=0 would be incorrect.
 
confused

Hi Gentec
That's a very interesting question -- have you ever been in a room with zero sound from two speakers.
Although they are waves they are Longitudinal I cannot see how such two waves can cancel (in front of one speaker ) being that their directions are very different -- by destructive do you mean minimal sound or zero sound ?
Transverse waves ( to me can cencel irrispective of direction ) but longitudinal I can only see cancelling if they are in the SAME direction .
As I say confused
Ray.
 
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