Which of these are practical applications of total internal reflection in our day to day life?
Optical fibre cables for communication
Endoscope
Total internal reflection is used in optical fibre cables. Through optical fibres, thousands of signals of different frequencies can be sent to distant places simultaneously, making use of total internal reflection of light, without the loss of intensity.
Also, when the optical fibre was first invented, it was used in the field of medicine for constructing a device called endoscope.
Diamond is very dense and it has a high refractive index. Therefore when light enters a diamond, the possibility of it being subjected to total internal reflection is very high, which causes a diamond to sparkle.
Twinkling of stars is due to refraction of light. Different layers in atmosphere have different refractive idices. Therefore the light coming from a star undergoes refraction when passes through these layers of atmosphere. This causes the light from the star to twinkle when seen from the ground.