Question

(iii) Define total internal reflection of light. Name the devices in which
internal reflection of light is used.​

Answer 1

Answer:

If angle of incidence is greater than the certain limit called critical angle then total internal reflection takes place .

example =diomand

Answer 2

Answer:

Total Internal Reflection

When the light in a denser medium strikes an interface seperating the denser medium and a rarer medium at an angle of incidence greater than the critical angle, total light is reflected without any retraction through the rarer medium. This phenomenon is called "Total Internal Reflection"

"Total Internal Reflection is obtained when ray passes from denser to rarer medium"

Device in which total internal reflection of light is used is: Optical Fibre

Optical fibre is a transmission medium to carry the optical signal without any appreciable loss. The structure of optical fibre consists of a core surrounded by cladding. Core is denser medium of refractive index μ$_{1}$ and cladding is relatively rarer medium of refractive index μ$_{2}$ such that μ$_{1}$ > μ$_{2}$. When light incident at one end of the core gets refracted and will bbe incident on the interface between the core and cladding at an angle greater than the critical angle and light continues reflecting in the core.