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Why does a wave reflect on the edge of an open tube? There is nothing solid to make the wave bounce.

Then why is it reflected?


marked as duplicate by Qmechanic Sep 15 at 22:51

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The boundary condition is that the sound pressure is zero there.

  • $\begingroup$ Is pressure zero? what do you mean... $\endgroup$ – molo32 Sep 15 at 18:48
  • $\begingroup$ The pressure there is given by the ambient pressure (for example 1 atm). This gives that the sound pressure is (almost) zero there, much smaller than inside the tube. So for the sound pressure, this is a fixed end. $\endgroup$ – Pieter Sep 15 at 18:57
  • $\begingroup$ @Pieter The pressure variation about atmospheric pressure is zero. $\endgroup$ – Farcher Sep 15 at 19:21

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