Joseph Henry is the only physicist
who has ever had a serving US President as his lab
assistant. Late at night, Abraham Lincoln often assisted
Henry with experiments.
is the energy per unit volume stored in E
or B fields. So we can store energy either in electric
or in magnetic fields, or in both at once.
A superconducting LC circuit behaves like an
undamped harmonic oscillator! The energy is just traded back and
forth between capacitor and inductor, in other words swapped
freely between electric and magnetic fields!