Question

Explain how will the power of a lens change when its surrounding medium is changed from air to water.

Answer 1

As we know for all the mediums the speed of the light is not constant at all$.$ The speed varies due to the optical density of the medium$.$ Optical density is basically inversely proportional to the speed of light which passes through the medium$.$

So the optical density is more than that air$.$ It has been found out that the speed of the light in the air$.$ It has been found out that the speed of the light in the air $3\times {10}^8$ and in the glass is $2\times {10}^8.$