Question

light enters through diamond which have refractive index 2.42 calculate the speed of light in diamond ,the speed of light in air is 30 X 10⁸ m s^-1

Answer 1

refractive index of diamond (n) = speed of light in vacuum (c) / speed of light in diamond (v)

or

n = c / v

or

v = c / n

here

n = 2.42

c = 3X 10⁸ m/s

so, the speed of light in diamond will be

v = (3X 10⁸) / 2.42

or

v = 1.23 X 10⁸ m/s