Two plane mirrors are inclined at angle ${40}^{\circ }$ between them. Number of images seen of a tiny object kept between them is_____.

A concave mirror of curvature $40 \mathrm{cm}$, used for shaving purpose produces an image of double size as that of the object. Object distance must be :

Choose the correct option.

Which of the following aberrations will NOT occur for spherical mirror ?

Consider the following phenomenon/ applications :

P) Mirage Q) Rainbow R) Optical fibre and S) Glittering of the diamond.

Total internal reflection is involved in_____?

Choose the correct option.

A student uses spectacles of number $-2$ for seeing distant objects. Commonly used lenses for his/her spectacles are_____.

Choose the correct option.

A spherical marble, of refractive index $1.5$ and curvature $1.5 \mathrm{cm}$, contains a tiny air bubble at its centre. Where will it appear when seen from outside?

Choose the correct option.

Select the WRONG statement.

Choose the correct option.

Angles of deviation for extreme colours are given for different prisms. Select the one having maximum dispersive power of its material.