Wussup with Ammeters and Voltmeters?

A shout-out to Anja, for producing this video explaining how ammeters and voltmeters are set up, i.e. what the circuitry is in order for these devices to give us measurements of currents and voltage differences. Many thanks!

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How to do the Math of LC Circuits

Interesting things happen when you combine loops of wire and metal plates in series. Inductors and capacitors together create AC currents at tunable frequencies, which in principle is the essence of our wireless society. In classical physics, the easiest way to create electromagnetic radiation is to accelerate (such as by shaking) electric charges, and that is exactly what you have in an AC current. Check this out to remind you of the math, and how LC circuits are the equivalent of simple harmonic motion of masses on springs from mechanics.