diff --git a/content/physics/thermodynamics.md b/content/physics/thermodynamics.md
index 6cf628b..119ecd5 100644
--- a/content/physics/thermodynamics.md
+++ b/content/physics/thermodynamics.md
@@ -57,4 +57,13 @@ $$
 
 Provides the power per unit area of the black body, from the interval $\left[\lambda, \lambda + \mathrm{d}\lambda\right]$, given that $\mathrm{d}\lambda$ is an infinitesimally small quantity. 
 
+## Wien's displacement law.
+
+Wien's law states the wavelength of peak intensity at a given temperature in Kelvin $T$ is given by:
+
+$$
+\lambda_{\text{peak}}=\frac{b}{T}
+$$
+
+Where $b$ is Wien's displacement constant, equal to $2.897771955\cdot 10^{-3} \mathrm{m}\cdot\mathrm{K}$.