SOME EXAMPLE OF TOTAL INTERNAL REFLECTION IN DAILY LIFE

1-) SPARKLING VISION OF A TEST TUBE PARTIALLY FILLED WITH WATER : Rays of light fall on the test tube where there is no water and gets reflected into air. As the test tube is tilted gradually, angle of incidence also increases. When the angle of incidence becomes more than 49, then total internal reflection takes place from this part of the test tube and it glows like silver. 

If test tube is completely  filled with water, then it does not happen because now critical angle becomes more than 49 and hence total internal reflection does not take place.

2-) BRILLIANCY OF DIAMOND : Refractive index of diamond with respect to air is 2.4 and critical angle for diamond and air is 24. When light falls on diamond it gets refracted and enters in it. The surface of the diamond are cut in such a way that, inside the diamond, the ray striking the surface makes an angle of incidence always greater than 24. Due to this, multiple total internal reflections takes place inside the diamond and the ray comes out in specific direction. If we look at from this direction then it appears shining.

3-) SPARKLING OF A CRACK IN GLASS : When the glass is cracked, then a thin layer is formed in cracking. Due to total internal refraction, the crack in glass is sparkled. 

4-) A PENCIL DIPPED IN WATER APPEARS TO BE SHORT AND BENT AT THE SURFACE IF SEEN FROM SIDE : A straight pencil is immersed in water. The portion BC appears to be shorten and bent as BC'. It is due to refraction. Virtual image of C formed at C'. Thus part BC appears to be BC'. Thus portion of stick under water appears to be raised and bent at point B.

5-) THE MIRAGE : On the hot summer day, a traveler in a desert region often sees a water with the trees and sky reflected in it, a short distance ahead of him. As he goes ahead, the lake disappears and he finds only a tree in the hot sand. This optical illusion is called mirage. Mirage can even be seen on road on a hot summer day the road at a distance appears to be covered with water, and we can see the reflection of sky and other objects from a distance. But as we approach the place where the water appears to be, we find that there is no water at all, and that it was just an illusion.  The phenomenon of mirage is produced by the total internal reflection of light which takes place when light passes from optically denser cold air to optically rarer hot air in the atmosphere.

6-)LOOMING : In cold countries the image of ship appears hanging inverted in air. This phenomenon is called looming. 

The layer of air in contact with earth is cooler and denser than layers above. so rays of light coming from ship pass from denser to rarer layers progressively and they get deviated away from the normal. so angle of incidence for every layer successive layer goes on increasing. A stage is reached when this angle and ray gets totally internally reflected. After reflection it reaches viewer's eye. To the viewer it appears that the whole ship is hanging in the air.