25.5.09

Maxwell's equations, or when to shut up

Professor James Clerk Maxwell, 1831-1879: dude united electricity and magnetism in Maxwell's equations, and taught pretty fucking close to where i live, at Marischal College, part of the University of Aberdeen (wasn't at the time, but whatever.) his equations for electromagnetism are based on Gauss, Ampere and Faraday's work; Maxwell synthesised their ideas into a unified theory. smart dude.

so i'm sitting in Physics 2512 a while ago, learnin' about said smart dude and how he's ONE OF US SILVER CITY SCUM and therefore even smarter by comparison, surrounded by physics majors whose intellectual acumen for the subject far exceeds mine (mine's limited to generating overly verbose descriptions of lessons rather than actually absorbing them.) luckily, i've sat next to dumbfuck, who would've made a good gymnast or something but is definitely not a physicist - beautiful, thin and clearly not getting it. even more luckily, i'm none of that there triad.

"I don't get how an electric field and a magnetic field can be the same." dumbfuck shuffles her papers in disgusted bafflement at the very idea.

"It's not," i say (i talk like i type, monotonously and drug-addledly.) "Electric fields generate magnetic fields, vice versa." it's a tutorial class, so to my excitement and everyone else's chagrin, we're allowed to talk, which means i'm allowed to inflict my shit on other people. "If you make a magnetic field change, it makes an electrical field. You make an electric field change, you get a magnetic one." i am of course paraphrasing Wikipedia's Maxwell's equations, but she doesn't know that. she sorta nods. cool, i think, you're teaching, Lepht!

so i carry on. "That's how this RFID chip works," i explain, and i poke the chip under my skin (you can see it move, and it's visible at rest too since the anaemia got bad.) "Reader emits an electrical field, generates a magnetic go-between field, generates another electrical field in the chip. Chip sends an identification value to the reader - no batteries," and i must've sounded pretty proud of that, i guess, even though i didn't have fuck all to do with creating it. "It's passive power. Never runs out."

i coulda stopped there, since dumbfuck was looking pretty freaked out (she turned out to be one of those doesn't-like-subdermal-stuff squeamies), but no, my stupid ass decided to carry on. "That's how all these neodyms work as well," and i continue my in-your-face poking of various non-flesh body parts. "You get near an EM field, it generates a little current in 'em, makes your hands tingle. Like this," and i hit Ctrl-C on my notes, point to the spot under the backtick key where the HDD is, "you can tell if the hard drive is active that way. It's cool, no?"

she did not think it was cool. i gotta learn when to shut the fuck up.

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