This basically assumes you have traveled through time because George Carlin handed you a time machine and you’re almost too stupid to breathe, or you went through a time rift, or some topologically similar scenario. Because if you invented a #@&^! time machine, you should know most of what’s there.
A moving electric field produces magnetism, and vice versa. Wrap copper around an iron core and run electricity through it, and you’ve got an electromagnet
What I’d want is an old chemistry book that included descriptions of how to obtain and purify chemicals, because that’s knowledge that’s been outsourced.
Well, it also assumes that you’re not going *too* far back into the past (or future), otherwise that trick with Polaris won’t work. And you need to be in the northern hemisphere as well.
Ooh, I got one nice old chemistry text book, “Elements of Chemistry” from 1953, which is really nice and explains many processes to obtain chemicals and other products, like soap and cellophane. I had found it in my home a long time ago. A few years later I found the lab manual to accompany it on abebooks. (I think you might be able to find some old chem books there too.)
Know how to make steel (both tough and hard), a lathe, a carbide cutting tool, and a decent steam engine. That will make you a god within a few iterations by economics or by guns.