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"Using the rope...start a crest at A. At the moment of its reflection at B as a trough, start a second crest at A. The trough and crest will meet near the middle of the rope. the rope particles at this point, being thus simultaneously acted upon by opposite forces, will remain at rest or nearly so." -Avery 1895

Destructive Interference

"Using the rope...start a crest at A. At the moment of its reflection at B as a trough, start a second…