In the above video we study the reflection
of a wave at an open (loose) end.
The blue line at the bottom of the video indicates
the position of the front of the reflected pulse.
Notice that after reflection the incoming wave and the reflected wave
interfere with each other in such a way
that at some places the amplitude becomes twice as large,
but at other places the amplitude vanishes.
However, besides that we observe only oscillations
in the part where the two waves interfere.
No wave seems to move to the left or to the right.
That phenomenon is called a
standing wave.
In contrast to the case of reflection at a fixed end,
in the case of reflection at an open end
the red object oscillates more heavily
when the two waves interfere than when just the incoming wave passes by,
whereas now the blue object does not
move much in this example.
Notice that at the open (loose) end the amplitude is maximum.
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