Electric and magnetic fields VS electromagnetic waves

mercredi 26 février 2014

Capacitors are popular candidates for explaining electric fields. The phenomenon becomes really apparent with the aid of a leiden jar ...which is really just a capacitor. Anyways, as long as you're cranking the handle on the electrostatic machine, the charge is going to build and build until I complete the circuit (just assume I'm holding a leiden jar that's connected to an electrostatic machine, in which you are operating).



Questions



Charge is flowing, correct? And if we define electricity as a flow of charge, then this^ is electricity, correct? And if so, you do NOT need a completed circuit for electricity to flow.



How exactly does electricity flow? Probably not how you think. It's easiest to imagine a group of people (atoms) that have gathered themselves into a circle (circuit). Every person has a ball (electron). Now tell everyone to pass their ball to the left. Of course, I'm forgetting things like voltage and current, but I think you get the idea.



Does anyone see where I'm going with this? What happens when you have an incomplete circuit like the leiden jar? How is that last atom (last atom at the end of my hand holding the jar) going to feed the first atom (wherever that is) an electron? Does the whole basketball paradigm break down? Kind of. What actually happens is electrons are sucked up through my feet. Okay. So exactly how far away in/on the ground are atoms passing electrons towards you? I don't know?! 20 yards, 2 feet, 7 inches from the last atom in my right foot. Lol, I'm not sure you can definitely answer that question. You're probably laughing, but I've seen some pretty crazy maths on this forum, so I'm asking whether it's theoretically possible to do such calculation.



I want to understand fields better. So, a static electron has no field, correct? But once set in motion, this electron takes on a new identity called a charge, and surrounding this charge is a field.



Sounds right, but I'm forgetting the part where once set in motion, you actually get electromagnetic interaction which radiates outwards. So I guess once set in motion, you get electromagnetic interaction, and then when the charge is in motion, you just get a field surrounding the charge ...that's flowing in the conductor.



I'm going to take a big leap here and ask why? Why the electromagnetic radiation the instant the charge is set in motion? I'm pretty sure it has to do with relativity. Once the charge is in motion, there will be no electromagnetic radiation radiating outwards. Why? The whole idea of what it means to be at rest. I assume once those charges are moving, then one can argue that they are at rest, and it is everything else that is moving.



I haven't introduced magnets yet, but maybe it's best I stop here.





0 commentaires:

Enregistrer un commentaire