What is Electricity?

#1

Post by SunSparc » Fri, Oct 16, 2015, 3:55 PM UTC

What is Electricity?
learn.sparkfun.com

Re: What is Electricity?

#2

Post by SunSparc » Fri, Oct 16, 2015, 3:57 PM UTC

Great little intro to electricity. SparkFun has some good educational tutorials.

Re: What is Electricity?

#3

Post by erehweb » Fri, Oct 16, 2015, 4:29 PM UTC

There is a story (perhaps apocryphal) that a student at Cambridge [?] was asked this at an exam many years ago.

He said "I'm sorry, I did use to know, but I've forgotten".

"How very unfortunate," said the professor. "In all of history, only two people have known what electricity is. One the creator, and the other yourself. And now one of the two has forgotten."

Re: What is Electricity?

#4

Post by SunSparc » Fri, Oct 16, 2015, 4:39 PM UTC

erehweb wrote: post #3

There is a story (perhaps apocryphal) that a student at Cambridge [?] was asked this at an exam many years ago. He said "I'm sorry, I did use to know, but I've forgotten". "How very unfortunate," said the professor. "In all of history, only two people have known what electricity is. One the creator, and the other yourself. And now one of the two has forgotten."

Haha, I daresay that student did poorly on the exam.

Re: What is Electricity?

#5

Post by murbard2 » Fri, Oct 16, 2015, 4:58 PM UTC

I would understand the material better if it were presented as an armadillo analogy. http://smbc-comics.com/index.php?id=3892

Re: What is Electricity?

#6

Post by dspillett » Fri, Oct 16, 2015, 5:24 PM UTC

Electricity is a myth.

Everything is really run by blue smoke and your cables are tubes to move it around. The wire inside the cable is just for strength.

You can see this is true when something shorts. The resulting hole in the system allows some blue smoke to escape, and the machine then stops working.

Re: What is Electricity?

#7

Post by 0xdeadbeefbabe » Fri, Oct 16, 2015, 5:36 PM UTC

Electricity is being in love. Feynman possibly agrees? http://www.lettersofnote.com/2010/06/you-dont-understand-ord....

Re: What is Electricity?

#8

Post by mrow84 » Fri, Oct 16, 2015, 5:41 PM UTC

Is it possible for signals to propagate as waves, without the electrons moving between atoms? Kind of like in this gif, but without them hopping along?

https://cdn.sparkfun.com/assets/9/5/6/1/4/519fcd42ce395f804c...

Re: What is Electricity?

#9

Post by heatish » Fri, Oct 16, 2015, 5:41 PM UTC

I've always wondered about the design choice for the shape of batteries. It seems like the shape would indicate the current is flowing the opposite way than it does. Something about the positive terminal just says to me "I'm shooting electrons this way"

Re: What is Electricity?

#10

Post by digi_owl » Fri, Oct 16, 2015, 5:46 PM UTC

heatish wrote: post #9

I've always wondered about the design choice for the shape of batteries. It seems like the shape would indicate the current is flowing the opposite way than it does. Something about the positive terminal just says to me "I'm shooting electrons this way"

I got the impression from somewhere that plus and minus was defined long before they could track actual electrons, and thus discover that they had them backwards.