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Homework Help: Destructive Interference Question

  1. Apr 20, 2010 #1
    Light Question
    1. The problem statement, all variables and given/known data

    A student enters Best Buy prepared to buy a pair of speakers. Before he does so, he conducts an experiment with them. He places the speakers 4.0 m apart and connects a signal generator to both speakers that produces a single and consistent tone. (constant wavelength and frequency) He then walks to a point that is 2.0 m from one speaker and 2.3 m from the other. At that point he notices a quiet “spot”. If the speed of the sound in the room is known to be 350 m/s, calculate the possible frequencies being played by the speakers.

    2. Relevant equations

    3. The attempt at a solution

    I don't even know where to begin. I don't even know how to go from speed to frequency. Thanks for any and all help
  2. jcsd
  3. Apr 20, 2010 #2


    User Avatar
    Homework Helper

    What's the condition for destructive interference?

    For a wave, speed, frequency, and wavelength are related by v=f*lambda.
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