The circuit depicted is in thermal equilibrium with its surroundings at a temperature \( T \). The classical formula for the root mean square (RMS) current flowing through the inductor is
1
\( I_{\text{RMS}} = \sqrt{\frac{3kT}{L}} \)
2
\( I_{\text{RMS}} =2 \sqrt{\frac{kT}{L}} \)
3
\( I_{\text{RMS}} = \sqrt{\frac{kT}{L}} \)
4
\( I_{\text{RMS}} = \sqrt{\frac{kT}{2L}} \)