Physics · Study 015
Ripple Tank
A real-time ripple tank: raindrops and your pointer launch circular waves that spread, reflect off the walls and interfere on a grid.
What you're looking at
The water surface is a grid of heights. Each cell's next height comes from the average of its four neighbours minus its own previous height, with a touch of damping. That short rule is a discrete wave equation, and it reproduces spreading rings, reflection at the edges and interference where rings cross.
The idea behind it
Physics classrooms use glass bottomed ripple tanks lit from above to show wave behaviour that is hard to see in sound or light. Shading here follows the slope of the surface, the way light refracts through real ripples to form bright and dark bands on the table below.
Try this
Drag across the water to draw a wake, or click for a single drop. Rain falls on its own.
