Question

I know Refraction is the bending of light when it enters another medium and changed speed but how exactly does the direction it bends vary when light is shone through a glass prism

Answer 1

It has to do with photons as they pass through the dense medium to a less dense medium. This causes the light that you shone through the glass pyramid to disperse and deviate into different angles based on its wavelength and that is why you sometimes see the rainbow colors after.