Light rays

Abstract

This chapter focuses on light, which is an electromagnetic wave and the straight line paths followed by very narrow beams of light, along which light energy travels, are called rays. The behavior of light rays may be investigated by using a ray-box. This consists merely of a lamp in a box containing a narrow slit that emits rays of light. When a ray of light passes from one medium to another, the light undergoes a change in direction. This displacement of light rays is called refraction. Lenses are pieces of glass or other transparent material with a spherical surface on one or both sides. When light is passed through a lens it is refracted. An image is the point from which reflected rays of light entering the eye appear to have originated. A compound microscope is able to give large magnification by the use of two or more lenses.