Recent content by bmhiggs

How does that affect the LED? Is it just a case of the frequency of the current being high enough that you can't tell the light is blinking? Any idea why it would have been manufactured that way? Based on the other components of the circuit, a DC current from a regular (dipole) ring magnet...

I posted this thread over on the physics forum, and no one could help me... https://www.physicsforums.com/threads/multipole-ring-magnet-generator.1057756/ Anyone here want to take a crack? It is probably more in the engineering wheelhouse.

It's just a coil of wire with a spinning magnet on top. The gear spins the flywheel, which houses the magnet, and rotates above the spool of fine copper wire. The copper wiring is connected directly to the lightbulb (no resistor, capacitor, etc.) I guess this is more of an engineering question...

I've dissected a pig (flashlight) and found a hand crank generator that has a multipole ring magnet. I used a bar magnet to establish that it was a multipole magnet, because I was wondering if I could figure out the direction of the current based on the direction of the magnetic field. My...

I did some more reading (ref this post: https://physics.stackexchange.com/questions/645817/why-is-there-no-electric-field-in-the-ideal-wire#:~:text=The%20wire%20has%20the%20same,voltage%20and%20no%20electric%20field. ) Also some hyperphysics...

Ok, before anyone wastes time on that last one, I did a quick search and found this: Why is the voltage drop across an ideal wire zero? - Reddit Reddit https://www.reddit.com › AskPhysics › comments › why... So disregard. But then I am back to the question of WHY a resistor DOES do work.

Ok: But: How can there be a current without an electric field?? Or is that vector E referring to something more specific? [Keep on exercising patience with me here if that should be obvious...]

But isn't that happening everywhere in the circuit? Why does a filament light up but the copper wire carrying the current does not? The current and E field are the same everywhere in the circuit, as has been amply shown by this thread. @sophiecentaur Any help here?

I'm trying to understand it from a conservation of energy standpoint... how does the resistor pull energy from the field and turn it into heat/light? This was a helpful example - but then the energy gets transferred by the work of the chain on the gear. Where does the work occur in a resistor?

This has been an extremely helpful series of explanations. Thanks for helping me go beyond what I took from two semesters of college physics and rereading several high school textbooks. One thing that has been especially clarifying is: Thanks @sophiecentaur ! Basic textbooks are always...

Sorry - I should have clarified that I was talking about series circuits, and I guess I mean atomic, not quantum.

Ohm's law states that current is inversely proportional to resistance, but on the quantum level, why does that actually slow the current down for the whole circuit? In all of the basic explanations, it talks about how the more densely packed matter in the resistor creates more collisions and...

Thanks!! That helps!

Nice - I'm more wondering about just the physical connections though. For clarification, the invention under discussion would just be for a handheld flashlight (I'll add that to the original post.) So power and efficiency aren't as important. Could you just solder the lead wires of the generator...

Can you give some more info there? I'm assuming a small DC generator (basic hand crank kind).