Question

What happens to light when it hits fx glas?
I want an explanation about reflektion and refraction.

Answer 1

Reflection is the returning, or "bouncing" of a wave off of a surface which resists that kind of wave. When it reflects, it always does so at the exact same angle it came in at. If you shine a light directly at a 90 degree angle, it will come directly back at a 90 degree angle. If you shine it 45 degrees to the left, it will exit 45 degrees to the right.

Refraction is the change in direction of a wave when it passes into a new substance. The reason the light changes direction or "bends" is because each different substance has it's own effect on the speed of light within itself. Every substance has an optical density, this number, called the substance's index of refraction, is how well light passes through it, the higher the density, the harder time light has moving through it.