1.0 Introduction

  Refraction of Light

When a ray of light passes from one medium to another, in which it has a different velocity, there occurs a change in the direction of propagation of light. This bending of light is known as refraction of light.

• When the ray of light strikes the surface of two media normally, it goes undeviating.
• The angle made by the incident ray with the normal is known as the angle of incidence. It is denoted by the symbol $i$.
• The angle made by the refracted ray with the normal is known as the angle of refraction It is denoted by the symbol $r$.
• The angle made by the emergent ray with the normal is known as the angle of emergence. It is denoted by the symbol $e$.