Question

Light enters from air into diamond which has a absolute refractive index of 2.42.if the speed of light in air is 3*10^8m/s,find the speed of light in diamond

Answer 1

μ = Speed of light in air/speed of light in medium
=> 2.4 = 3 * 10^8/ speed of light in diamond
=> Speed of light in diamond = 3 * 10^8/2.4
=> 1.25 * 10^8 m/s

Answer 2

Speed of 'light' in 'diamond' is $\bold{1.24 \times 10^{8} \mathrm{m} / \mathrm{s}}$

SOLUTION:

The refractive index of an object defines the property the material will show when a light will get refracted from the surface. The exact value in relative to the other refractive index of the other surface is known as absolute refractive index.

Here the value of absolute refractive index is given as:

RI (r) = speed of light in air(c)/speed of light in medium (a)

r= c/a

a = c/r  

$a=\frac{3 \times 10^{8}}{2.42}$

$\mathrm{a}=1.24 \times 10^{8} \mathrm{m} / \mathrm{s}$