Question

What is total internal reflection and give an example?

Answer 1

TIR - total internal reflection is the phenomena of reflecting back of light from a surface when light is incident on an angle greater than the critical angle and light travels from denser to rarer medium.

The reflection of light in a prism follow TIR.
Light is incident on the surface of prism at an angle greater than critical angle and reflects inside the prism again and again.

Answer 2

WHEN A RAY OF LIGHT PASSES FROM A MEDIUM OF HIGHER OPTICAL DENSITY TO A MEDIUM OF LOWER OPTICAL DENSITY AT AN ANGLE OF INCIDENCE GREATER THAN THE CRITICAL ANGLE,THE RAY IS REFLECTED BACK TO THE SAME MEDIUM WITH OUT UNDERGOING REFRACTION.THIS KNOWN AS TOTAL INTERNAL REFLECTION. ..