Question

What is meant by wave number ?​

Answer 1

Answer:

Wavenumber, also called wave number, a unit of frequency, often used in atomic, molecular, and nuclear spectroscopy, equal to the true frequency divided by the speed of the wave and thus equal to the number of waves in a unit distance. ... This number is called the wavenumber of the spectrum line.

Answer 2

Wavenumber

$\red\implies$The wavenumber (k) is simply the reciprocal of the wavelength, given by the expression. k = 1 / λ

$\purple\implies$The wavenumber (k) is therefore the number of waves or cycles per unit distance.