devarshi-dt-logo

Question:

A biconvex lens made of a transparent material of refractive index 1.5 is immersed in water of refractive index 1.33. Will the lens behave as a converging or a diverging lens?

Solution:

A biconvex lens behaves as a converging lens in air because the refractive index of the material of the lens is greater than the refractive index of the air. The refractive index of the material of the lens (1.5) is also greater than the refractive index of water (1.33). So, it will behave as a converging lens.