Light
is a source of energy that travels in a straight line and it can be bent
slightly through water. This is called refraction.
Refraction
occurs because light bends. A lens is a piece of transparent
material. It is usually made of glass and has at least one curved
surface. Look at the convex and concave lenses below.
The
curved surface/surfaces of a lens bends the light. Notice the paths of
light of the convex and concave lenses shown below.
