Question

 Write the Wiedemann Franz law.

Answer 1

Wiedemann-Franz's law - the statement that the ratio of the thermal conductivity to the electrical conductivity of a metal is proportional to the temperature:

$\frac{k}{\sigma}=(\frac{\pi^2k_b^2}{3e^2})T=L\cdot T$ ,

$k$ is the thermal conductivity;

$\sigma$ is the electrical conductivity;

$L$ is the Lorenz number.