This simulation demonstrates interference of waves from two identical sources that are separated by a variable distance. The wave crests are shown in green and the troughs in purple, with black indicating a local wave amplitude of zero. (Note that the entire image updates instantly when you move the slider, because it is drawn using a formula that assumes fixed separation, rather than from a simulation of the time-dependent response of the wave medium. Note also that the wave amplitude does not decrease with the distance from the source, as it would for physical waves.)
This simulation is also intended to demonstrate pixel-by-pixel image creation for the HTML5 canvas element using the putImageData function.
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