Question

a plano convex lens n=1.5 and radius= 15 cm. find focal length​

Answer 1

Explanation:

The lens maker's formula is:

1/f =( n-1){(1/R1) -(1/R2)},

where n is the refractive index of the material of the lens with respect to the medium in which it is placed, R1, R2 are radii of curvature of the two surfaces of the lens.

Let us the refractive index of material of the lens with respect to air is 1.5, and R1 =15 cm and R2= infinity ( for the plane surface),

Substituting, these values we get,

f =30 cm =30/100 m =0.3 m

Therefore power of the lens=1/0.3= 3.33 diopter

Answer 2

Answer:

above anser is absolutely correct ✅