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Free end of a string

  1. Aug 11, 2010 #1
    The free end of a classical vibrating string imposes the boundry condition that the spatial deriviative of the string at the end must be zero. I can hand wavingly argue this with free body diagrams and manipulate the differential force approximations but i cant come up with a terse intuitive explanation of this boundry equation. any help?
  2. jcsd
  3. Aug 11, 2010 #2


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    Another way of getting the result is that there is a 100% reflection of any disturbance propagating toward the end, and this reflection is uninverted. When you sum the incident and reflected waves, y(x) doubles, but y'(x) cancels.

    This question belongs in the Classical Physics forum.
  4. Aug 11, 2010 #3


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