Chapter 62: Chapter 62 A Growing Spark

Stella was immediately engaged, coming over to study the machine in detail. After a minute, she looked perplexed. “Ok. What does this have to do with lightning?”

Nathan pointed to the two wires coming off of the brush. “When I spin this handle, those wires will get charged. Not strongly - you would need to touch them together for there to be a spark. But this device is a way to demonstrate the basic principles I was talking to you about.

Aarl complained from the side of the room. “She merits a warning. I understand the lay of the land. I just get shocked.”

Stella turned and stuck her tongue out at Aarl, but turned back quickly, studying the machine. She grabbed the two wires and gestured for Nathan to start turning the crank.

He leaned his back into it, spinning up the generator and keeping it moving fast. Stella started tapping the wires together, giggling as small sparks zapped. After a minute, he slowed down and the sparking stopped.

Stella stood up, excited. “Ok! Great. So, tell me how this works!”

Nathan grabbed a slate, and sat down. “Ok, so I told you before that when you have a moving magnetic field, that creates an electric field, right? That’s what’s going on here. It’s invisible, so you can’t see the field. But I can draw about what they would look like. Now, before we start looking at why that happens, we need to go over the basics of how electric and magnetic fields work.”

Nathan pulled out the two magnets and handed them to Stella. “Have you run across these before?”

Stella blinked, then took the magnets, sticking them together and then pulling them apart with a bit of effort. “Yeah, though they’re not used for much. Not magical, and they mess with some kinds of magic in weird ways. My dad has a couple of them, but more as curiosity pieces than anything else.”

Nathan pointed at the magnets fastened to the inside of the generator, almost touching the spinning coils of copper wire. “They’re sources of magnetic fields, but not simple ones. Here, let me draw what it looks like.”

Nathan started explaining the basics of magnetic fields, sprinkling some iron filings around the magnet on a table to demonstrate how the filings gathered on the magnet. He spent a few minutes spreading them out, showing how they followed the magnetic field lines.

Now we’re in the meat of it, but this is still going to take a while.

---