Question

A convex lens made of a material of refractive index `n_2` is kept in a medium of refractive index `n_1`. A parallel beam of light is incident on the lens. Complete the path of rays of light emerging from the convex lens if
(i) `n_1 lt n_2` (ii) `n_1 = n_2` (iii) `n_1 gt n_2`.

Answer 1

When `n_1 lt n_2`, light goes from rarer to denser medium. Therefore, on passing through a convex lens, it converges,

(ii) When `n_1=n_2`, there is no change in medium.Therefore, no bending or refraction occurs as shown in figure.
(iii) When `n_1 gt n_2`, light goes from denser to rarer medium. Therefore, no passing through a convex lens, it diverges as shown in figure.