Question

A hollow lens is made of thin glass and in the shape of a double concave lens. It can be filled with air, water of refractive index 1.33 or CS2 of refractive index 1.6. It will act as a diverging lens if it is

(A) filled with air and immersed in water.

(B) filled with water and immersed in CS2.

(C) filled with air and immersed in CS2.

(D) filled with CS2 and immersed in water.

Answer 1

Correct Option :- (D) filled with CS2 and immersed in water.

Explanation :-

μair = 1

n2 > n1

∴ Lens should be filled with liquid which has more refractive index in comparison to liquid in which lens is immersed.

∴ Ans (D) is the correct option as

μcs2 > μwater