LIGHT: (reflection, refraction, mirrors, lenses, diffraction)

Just like the normal force, the normal line is drawn Perpendicular to the surface. The law of refraction is simply the conservation of momentum (It’s a collision at an angle). Demo: Tennis ball bouncing off a surface, the incident = reflection. One can solve this as an angled collision. Lets look at Reflection with Mirrors: Plane Mirrors ... ................
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