In the event the beam of sunshine is not orthogonal (or instead regular) to the boundary, the adjust in wavelength leads to a alter during the path with the beam. This variation of way is called refraction. John LawlerJohn Lawler 109k1111 gold badges185185 silver badges489489 bronze badges 3 1 https://damien71w36.bloggerbags.com/41943193/not-known-facts-about-smart-cases