Question

frequency of light wave in a material is 4×1014 hz and wavelength is 3000 A the refractive index of material will be​

Answer 1

refractive index of medium is 2.5

it has given that frequency of light wave in a material is 4 × 10¹⁴ Hz and wavelength is 3000 Å

we have to find the refractive index of material.

first find velocity of light wave in medium,

velocity of wave = frequency × wavelength

so, velocity of wave in the medium = 4 × 10¹⁴ × 3000 × 10^-10 = 12 × 10^7 m/s = 1.2 × 10^8 m/s

we know, velocity of light wave in vacuum = 3 × 10^8 m/s

now using formula,

refractive index of a medium = velocity of light in vacuum/velocity of light in the medium

= 3 × 10^8 m/s/1.2 × 10^8 m/s

= (3/1.2) = 1/0.4 = 2.5

therefore refractive index of medium is 2.5