A circular beam of light (diameter $=d$) falls on a plane surface of a liquid. The angle of incidence is $45°$ and refractive index of the liquid is $\mu$. The diameter of the refracted beam is

A beam of light consisting of red, green and blue colours is incident on a right angled prism. The refractive indices of the material of prism for the above red, green and blue wavelengths are $1.39, 1.44$ and $1.47$ respectively. The prism will

The optical density of turpentine is higher than that of water while its mass density is lower. Figure shows a layer of turpentine floating over water in a container. For which one of the four rays incident on turpentine in figure, the path shown is correct?

A car is moving with at a constant speed of $60 \mathrm{km} {\mathrm{h}}^{-1}$ on a straight road. Looking at the rear view mirror, the driver finds that the car following him is at a distance of $100 \mathrm{m}$ and is approaching with a speed of $5 \mathrm{km} {\mathrm{h}}^{-1}$.

In order to keep track of the car in the rear, the driver begins to glance alternatively at the rear and side mirror of his car after every$2 \mathrm{s}$ till the other car overtakes. If the two cars were maintaining their speeds, which of the following statement (s) is/are correct?

There are certain materials developed in laboratories that have a negative refractive index figure. A ray incident from air (medium $1$) into such a medium (medium $2$) shall follow a path given by