Page 4

So light changes direction when its goes in and out of glass. Where on earth might that be useful?

Well here are some light rays changing direction and what's that funny shaped thing in the middle? Its a LENS. It is jolly useful to be able to control the direction of light. Knowing about refraction helps us design optical instruments and make beautiful sparkly diamonds.

As Kevin tucks into a well earned sugar cube I bid you au revoir. (that's French for see you later)