Question

A beam of light parallel to the principal axis of a convex lens is incident on the lens. The refractive index of the lens is ng and that of the medium in which it is kept is nm. Draw a ray diagram to illustrate the refraction through the lens, given that nm is equal to ng.

Answer 1

Explanation:

Answer in the attachment

Answer 2

Given:

A beam of light parallel to the principal axis of a convex lens is incident on the lens. The refractive index of the lens is n_(g) and that of the medium in which it is kept is n_(m).

To draw:

Ray digram illustrating the refraction.

Solution:

Usually, we know that a convex lens (of glass) when kept in air acts like a converging lens.

• That means, parallel light rays after refraction will converge. Any type of light rays (diverging/parallel) will undergo some degree of convergence.

But know, a lens of refractive index $n_{g}$ has been placed in a medium of refractive index $n_{m}$.

So, whenever light rays will $\rm pa{s}s$ through the lens, they will undergo refraction but will not experience any deviation.

• This is because, there is no change in velocity of light during refraction through the lens.

Hope It Helps.