A convex lens of glass `(mu_(g) = 1.45)` has a focal length f in air. The lens is immerseJ in a liquid Of refractive index (`mu_(I)`) 1.3. The ratio of the `F_(“liquid”)/F_(a)` is is

Options

A. 3.9
B. 0.23
C. 0.43
D. 0.39

Answer

A

Explanation

The ratio of` f_(liquid)/(f_(a)) = (mu_(g)-1)/(mu_(g)/mu_(l) -1) =(1.45 – 1)/(1.45/1.3 – 1) = 0.45/0/11= 3.9`