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Homework Help: Where to start?

  1. Oct 30, 2011 #1
    Two sine waves have equal peak to peak amplitudes 81 but are out of phase by 90 degrees. What is the peak to peak amplitude of the resultant wave.


    I have no idea how to start this question, could someone give me guidance?
     
  2. jcsd
  3. Oct 30, 2011 #2
    Graph
    [tex]40.5sin(\omega t-\frac{\pi}{2})[/tex] and [tex]40.5sin(\omega t)[/tex]
    The points on the graph where these functions intersect are where the resultant will have its maximum (and minimum) amplitudes.
     
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