# What is Dimensional Formula of Wave number (Propagation constant) ?

Posted in Dimensional Formulae | Email This Post |Wave number can be defined as the number of waves per unit length. In other words it is number of waves that occurs across a fixed distance. It is also known as *propagation constant*.

Wavenumber is reciprocal of Wave length. Unit of Wavenumber are cycles per centimeter or inverse centemeters.

**Wave number (k) = 2 π / λ (Wave length) **

Dimensional formula of wavelength = M^{0}L^{1}T^{0}

So putting this value in the formula we get,

**Dimensional Formula of Wave number or Propagation constant = M ^{0}L^{-1}T^{0}**

SI units of Wave number or Propagation constant is m^{-1}.

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