# Electricity and Electromagnetic Waves **URL:** \ **Category:** Factual Questions\ **Created:** [December 1, 2015, 8:16pm UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141 "2015-12-01T20:16:33Z")\ **Posts on this page:** 9\ **Page:** 2
**Author:** ![CurtC](https://avatars.discourse-cdn.com/v4/letter/c/ce73a5/32.png) [@CurtC](https://boards.straightdope.com/u/CurtC)\ **Post date:** [December 3, 2015, 4:46pm UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141/21 "2015-12-03T16:46:32Z")
> [@carnivorousplant](#): > > We did an experiment bouncing a square wave between ends of a coaxial cable in undergraduate school, and determined that it was moving at .8C. Right, and that speed is completely a function of the insulator material on the inside of the coax cable. It’s not dependent on the metal that the conductors are made from, like many people might think because that’s where the electrons do their flowing thing. The speed down the cable is dependent on the insulator material, where the electromagnetic wave happens. ---
**Author:** ![CurtC](https://avatars.discourse-cdn.com/v4/letter/c/ce73a5/32.png) [@CurtC](https://boards.straightdope.com/u/CurtC)\ **Post date:** [December 3, 2015, 5:03pm UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141/22 "2015-12-03T17:03:05Z")
> [@Derleth](#): > > That’s entirely at odds with how everyone else defines the term, and it makes nonsense of various terminology. For example, the electromagnetic field has no amperage. An amperage is a flow of charged particles, and photons have no charge, so QED. Sure, but that was kind of my point. If you scratch the surface of what everyone learns in 8th grade, which is about electrons flowing and amperage, and ask what’s really going on underneath, things get interesting. And what’s underneath is the electromagnetic field, which causes electrons to move. This becomes apparent when you consider what I was saying about the speed of propagation down a cable or pair of wires. > [@](#): > > The electromagnetic field is everywhere, and is probably best thought of as just a computational tool. Right, which gets your layman off the street to then think: “but what IS the field really?” And the answer to that is, it’s just a model, and that’s all we can say. You can’t describe it in a way that it makes intuitive sense. I like to describe it this way because it really does get people to think in a new way. ---
**Author:** ![DrCube](https://avatars.discourse-cdn.com/v4/letter/d/a3d4f5/32.png) [@DrCube](https://boards.straightdope.com/u/DrCube)\ **Post date:** [December 3, 2015, 5:23pm UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141/23 "2015-12-03T17:23:38Z")
> [@carnivorousplant](#): > > We did an experiment bouncing a square wave between ends of a coaxial cable in undergraduate school, and determined that it was moving at .8C. Yeah, but light would travel at the same speed in the same dielectric medium. In other words the current still travels at the speed of light, it’s just that the speed of light in a coaxial cable is 80% of the speed of light in a vacuum. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [December 3, 2015, 7:27pm UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141/24 "2015-12-03T19:27:35Z")
> [@](#): > > But what about opposite-charged particles attracting each other? How do you explain that with photon exchange? I see at stackexchange that others are also confused and long eyes-glazing-over answers are available online, e.g. at math.ucr.edu/home/baez/physics. But is there a very simple explanation for simpletons? The simplest answer I can give for a layman is that in that case, the photons bouncing between them have a momentum in the direction opposite the direction of their motion. Which, yes, sounds crazy. But hey, nobody ever said anything in quantum mechanics was intuitive. ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [December 3, 2015, 7:37pm UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141/25 "2015-12-03T19:37:04Z")
> [@Chronos](#): > > But hey, nobody ever said anything in quantum mechanics was intuitive. 🙂 ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [December 4, 2015, 6:21am UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141/26 "2015-12-04T06:21:33Z")
Re: How do photons bouncing between particles create _attractive_ force between them? > [@Chronos](#): > > The simplest answer I can give for a layman is that in that case, the photons bouncing between them have a momentum in the direction opposite the direction of their motion. Which, yes, sounds crazy. But hey, nobody ever said anything in quantum mechanics was intuitive. The first link in **Derleth** ’s Post #15 above is a FAQ on virtual particles, with that being Question #2. The explanation there begins about one screenful into the page. Here’s the link again: [Some Frequently Asked Questions About Virtual Particles](http://math.ucr.edu/home/baez/physics/Quantum/virtual_particles.html) ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [December 4, 2015, 7:06am UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141/27 "2015-12-04T07:06:32Z")
> [@Senegoid](#): > > The first link in **Derleth** ’s Post #15 above is a FAQ on virtual particles, with that being Question #2. The explanation there begins about one screenful into the page. Okay, I just went and tried to read that. It’s actually a little bit technical, and seems to assume the reader knows at least a little something about it already. I couldn’t really understand it. ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [December 4, 2015, 12:30pm UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141/28 "2015-12-04T12:30:40Z")
> [@Senegoid](#): > > Okay, I just went and tried to read that. It’s actually a little bit technical, and seems to assume the reader knows at least a little something about it already. I couldn’t really understand it. Have you studied Fourier? Even in a simplistic form, Fourier theory is a key (at least to me) in understanding this. The duality between normal and frequency space, and the way Heisenberg’s Uncertaintly falls out of this is a very big part of this. If you can get your head around that, you can make progress with the rest. Unfortunately many commentaries jump straight into wavelike things and location uncertainly, assuming you understand why. ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [December 4, 2015, 1:35pm UTC](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141/29 "2015-12-04T13:35:03Z")
> [@friedo](#): > > The overhead wires are still using a frequency of 60Hz, but much higher voltage and current. . Not really a higher current per unit of circumference (skin effect, most current is in the surface.) In fact less, as copper doesn’t hang off poles really well. They do carry a larger current, as a wire hanging off larger pylons must be stronger… bigger… larger circumference… but its all proportional to size… The transmission lines carry a higher voltage in order to carry higher power, and yet avoid exceeding current carrying capability of the wire, and transmission losses… voltage transmits for free, the loss is related to current. [Previous page](https://boards.straightdope.com/t/electricity-and-electromagnetic-waves/739141.md?page=1)