Question

(a) Draw and label the diagram given :
(i) Incident ray
(ii) Refracted ray
(iii) Emergent ray
(iv) Angle of reflection
(v) Angle of deviation
(v) Angle of emergence
(b) The refractive index of diamond is $2.42$. What is the meaning of this statement in relation to speed of light?

Answer 1

(a) The labelled diagram is shown.

(b) The refractive index of diamond is $2.42$. Refractive index of diamond is the ratio of the speed of light in air to the speed of light in diamond.i.e.,

$\mu =\frac{Speedoflightinair}{Speedoflightindiamond}$

and, the ratio of these velocities is $2.42$. i.e., This means that the speed of light in diamond will reduce by a factor of $2.42$ as compared to its speed in air. In other words, the speed of light in diamond is $\frac{1}{2.42}$ times the speed of light in vacuum.