The figure given below shows an L C R series circuit with two switches S_1 and S_2. When switch S_1 is closed keeping S_2 open, the phase difference…

The figure given below shows an $\displaystyle L C R$ series circuit with two switches $\displaystyle \mathrm{S}_1$ and $\displaystyle \mathrm{S}_2$. When switch $\displaystyle \mathrm{S}_1$ is closed keeping $\displaystyle \mathrm{S}_2$ open, the phase difference $\displaystyle (\phi)$ between the current and source voltage is $\displaystyle 30^{\circ}$ and phase difference is $\displaystyle 60^{\circ}$ when $\displaystyle \mathrm{S}_2$ is closed keeping $\displaystyle \mathrm{S}_1$ open. The value of $\displaystyle \left(3 L_1-L_2\right)$ is $\displaystyle \_\_\_\_$ H.