Hi everyone, I've dealt with resonance (normal modes of a system) in a fair amount of detail, but it was in the context of a mechanics course. Now, I'm trying to extent this concept to electromagnetism, particularly LRC circuits, and I'm having a really hard time wrapping my head around it. I can't understand "what" is resonating, and the mechanism behind why it resonates. This area of physics has never been a strong point for me. Can anyone either provide a brief crash course or recommend any good books or websites that can explain this to me?