Ampere’s Law Demonstration

Okay, this is a demonstration of Ampere's law. A current creates a magnetic field. Okay, so first of all, over here to the left, I've got my potential difference. That's my transformer, like so. I then have it hooked up to this simple circuit, which really consists of nothing more than this wire. Okay, a portion of this circuit here is this L-shaped gold wire that you can see. And then on the platform there, it's a plastic platform. I have a couple of different compasses. Right now, all the compasses here are lining up roughly with the north-south magnetic field associated with the Earth that is present here in the classroom. Okay, now I'm gonna go ahead and turn on the current here. I'm gonna turn on the conventional current. And when I do, a force is gonna be exerted upon each individual compass needle, like so. And then if you look at the geometry here carefully, once all the compass needles settle down, what you will see is that all the compasses here, the compass needles, are now tracing on a circle. They're tracing on a circle that is centered on the current-carrying wire. So a moving electrical charge, that is a conventional current, for example, creates a magnetic field. This is the source of all magnetic fields. This is a simple demonstration of Ampere's law.