Total Internal Reflection

When the angle of incidence in the denser medium increases the angle of refraction also increases and it reaches a maximum value of r = 90° for a particular angle of incidence value. This angle of incidence is called the critical angle.
The angle of incidence at which the angle of refraction is 90° is called the critical angle.
When the angle of incidence exceeds the value of the critical angle, the refracted ray is not possible, since r > 90° the ray is totally reflected back to the same medium. This is called total internal reflection.
Condition for Total Internal Reflection
The LIght must travel from a denser medium to a rarer medium. Example: From Water to Air.
The angle of incidence inside the denser medium must be greater than than the critical angle. The angle of incidence inside the denser medium must be greater than the critical angle.
Total Internal Reflection in Nature
- MIrage in the road deserts on Summer days.
- Shining of Diamond.
- Twinkling of stars
Total Internal Reflection Uses
Optical Fibre Communication(OFC) for transmitting audio and video signals. Optical fibers are used in medical, by physicians to look and work inside the body through tiny incisions without the need for surgery.