Concepts of Physics

IIT JEE Physics (1978-2018: 41 Years) Topic-wise Complete Solutions

Coin vanishing under the water vessel


Coin vanishing under the water vessel.


Scattering and refraction can be effectively used to create very interesting viewing situations. This experiment is one such simple situation which everyone enjoys but the explanation is not very straight forward.


A cubical water vessel, a coin.


  1. Place a coin on the table and above that place the vessel. Look through a side surface. You can see the coin quit clearly.
  2. Now pour water in the vessel. See through the same side surface, this time light coming through water.
  3. Are you able to see the coin? Provide explanation of this phenomenon.