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Destructive Interference

  1. Dec 19, 2004 #1
    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
  2. jcsd
  3. Dec 19, 2004 #2
    destructive interference between two waves occurs at m+(1/2) where m=0,1,2,3,...

    so, m=0 would be incorrect.
  4. Dec 20, 2004 #3

    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
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