House & Home Physics
Pipe Pressure Drop (Darcy–Weisbach)
ΔP = f·(L/D)·(ρv²/2)

Friction loss in a supply line grows with the square of flow velocity — why a long, thin, high-flow run needs a bigger pipe or a stronger pump.
Computed & rendered in pure C# on the frozen OnlyCSharp 1.8 library — animation baked to GIF with the library's own
Gif encoder (no GPU, no ffmpeg, no external packages).