Monochromatic light of frequency $5 \times 10^{14} \ Hz$ travelling in vacuum enters a medium of refractive index $1.5$. Its wavelength in the medium is ....... $\mathring{A}$.

If light passes near a massive object,the gravitational interaction causes a bending of the ray. This can be thought of as happening due to a change in the effective refractive index of the medium given by $n = 1 + \frac{2GM}{rc^2}$,where $r$ is the distance of the point of consideration from the centre of the mass of the massive body,$G$ is the universal gravitational constant,$M$ is the mass of the body,and $c$ is the speed of light in vacuum. Considering a spherical object,find the deviation of the ray from the original path as it grazes the object.

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

$A$ ray of light is incident at the glass-water interface at an angle $i$. It emerges finally parallel to the surface of water. The value of ${\mu _g}$ is (given refractive index of water ${\mu _w} = 4/3$):

The velocity of light in glass,whose refractive index with respect to air is $1.5$,is $2 \times 10^8 \ m/s$. In a certain liquid,the velocity of light is found to be $2.5 \times 10^8 \ m/s$. The refractive index of the liquid with respect to air is:

$A$ light ray of frequency '$v$' and wavelength '$\lambda$' enters a liquid of refractive index $\frac{3}{2}$. The ray travels in the liquid with: