Ripple Tank Interference: Two/Three-Source Superposition (2D)

The 3D original renders circular ripples overlapping on an orbit-and-zoom water surface. This 2D companion keeps the same physics — a damped travelling wave summed from every coherent point source, evaluated exactly, not approximated — but drives it from a top-down view built for reading the interference pattern rather than admiring it: switch between two and three sources, drag their separation, a phase-step slider that turns the sources into a simple phased array, the wavelength and the distance-decay, then click anywhere in the tank to drop a probe. The panel reads off the true path-length difference at that exact point and tells you whether it lands on a bright constructive fringe, a dark destructive one, or somewhere in between — the same reasoning that explains the bands in a real ripple tank or a double-slit experiment, made directly measurable instead of only visible.