A convex lens has 12 cm focal length in air. What is its focal length in water? (Refractive index of air-water is `(1.33)`, refractive index for air-glass = `(1.5)`.

A convex lens has 10 cm focal length in air.What is its focal length in water? (Refractive index of air-water is 1.33, refractive index for air glass = (1.5)

A convex lens has 20 cm focal length in air.What is its focal length in water? (Refractive index of air-water is 1.33 , refractive index for air¬glass = 1.5).

An equiconvex lens has focal length equal to the radius of curvautre.Its refractive index is

A converging lens has a focal length of 20 cm in air. It is made of a material of refractive index 1.6. If it is immersed in a liquid of refractive index 1.3, what will be the new focal length? How does the nature of the lens change. If this lens is immersed is a liquid of refractive index 1.8 ?

Find the ratio of the powers of a glass lens in water and in air .Given,refractive index of glass =1.50,refractive index of water=1.33.

If refractive index of glass w.r.t. air is 1.55, then what is the refractive index of air w.r.t. glass.