When a test tube is immersed at a certain angle in a tumbler of water appears to have a mirror surface from a certain viewing positions due to total internal reflection.
Explanation :
- The critical angle for glass is 42°.
- The glass and air in test tube works as denser and rarer mediums.
- The rays of light while travelling through water strike glass – air interface of test tube at an angle of more than 42° (i > c) they get totally internal reflected as shown figure.
- When these reflected rays reach the eye, they appear to come from the surface of test tube itself.
- Now the test tube appears like silvary.
