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Homework Help: Interesting Problem, Not sure where to begin.

  1. Dec 2, 2004 #1
    I need some help getting started on this one:

    Sound waves of frequency 582 Hz enter a window 1.3m wide.

    The window is in the exact center of one wall of a theater 24m by 12m.

    The window is 12m from the opposite wall, along which is a row of seats occupied by people.

    The theater is acoustically prepared to prevent the reflection of sound waves, and the speed of sound is 330 m/s.

    Two people, on each side of a line directly in front of the window, in the row along the wall hear no sound.

    What minimum distance are they from each other?
     
  2. jcsd
  3. Dec 2, 2004 #2

    Andrew Mason

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    This is a 'single slit' diffraction problem. The first minima on the far wall will occur at a point x from the middle of the wall where [itex]x = \lambda L/a[/itex] where a is the slit width and L is the distance from the window to far wall.

    I get 10.5 feet.

    AM
     
  4. Dec 2, 2004 #3
    Wouldn't that correspond to the first maxima and not minima?
     
  5. Dec 2, 2004 #4

    Andrew Mason

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    I think the formula is for the first minima - this is single slit diffraction. You may be using double slit diffraction. I am sure you can check this.

    AM
     
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