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Homework Help: Deflection angle question

  1. Jan 30, 2010 #1
    When asked to find the deflection angle for an electron passing through a parallel plate capacitor, for some reason my initial approach was to find the horizontal distance travelled and the vertical distance and then find the angle created by them. I got the wrong answer doing this and looked at the solution which explained that you have to use the final vertical/horizontal velocities and the angle created by them. This makes sense to me, but I still don't understand why my method wouldn't work? Any clarification would be appreciated. Thanks!
     
  2. jcsd
  3. Jan 30, 2010 #2

    tiny-tim

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    Hi maccha! :smile:

    It's because you're finding the slope of the chord from entry to exit (which will be roughly parallel to the tangent at half-way), but the question asks for the slope of the tangent on exit, which is about twice as much. :wink:
     
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