A wavenumber is defined as the inverse of the wavelength of a wave. It represents the number of waves per unit length.
The formula to calculate the wavenumber (u) is:
\[ u = \frac{1}{\lambda} \]
Where:
Let's say the wavelength (λ) is 0.5 meters. Using the formula:
\[ u = \frac{1}{0.5} = 2 \text{ m}^{-1} \]
So, the wavenumber (u) is 2 m-1.