Question

If a LC circuit is considered analogous to a harmonically oscillating spring block system, which energy of the
LC circuit would be analogous to potential energy and which one analogous to kinetic energy?

Answer 1

If we consider an LC circuit analogous to a harmonically oscillating spring block system, the electrostatic energy $\frac{1}{2}CV{}^2$ is analogous to potential energy and energy associated with moving charges (current) i.e. magnetic energy $\left(\frac{1}{2}L{I}^2\right)$ is analogous to kinetic energy.

Final Answer:
Magnetic energy is analogous to kinetic energy and electrical energy is analogous to potential energy.