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What is Electricity?

learn.sparkfun.com

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Re: What is Electricity?

#21

Post by delinka »

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"

Something that bugged me as a kid trying to learn electronics: everything is connected to ground, negative is on ground, so we're dumping electrons onto every path in the circuit. It's the job of the resistor, capacitor, transistor, IC, etc, to direct those electrons, putting their energy to use, and then dumping them back to positive.

Re: What is Electricity?

#22

Post by snaky »

tim333 wrote: post #16
johncolanduoni wrote: post #14

Earlier quoted context omitted.

Wow, one of my favorite scientists dissing one of my least favorite. Thanks for the link!

That's quite funny. I see from Wikipedia Feynman was on Wolfram's PhD thesis committee. He can't have been too impressed with Wolframs people skills.

That skills are legendary https://www.reddit.com/r/programming/comments/8l3bq/wolfram_...

Re: What is Electricity?

#23

Post by 0942v8653 »

hga wrote: post #18
digi_owl wrote: post #10

Earlier quoted context omitted.

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.

Yes, Benjamin Franklin was the first to assign positive and negative, and got the sign wrong. It looks like it took around another century to figure out that detail.

https://xkcd.com/567/

Re: What is Electricity?

#24

Post by shostack »

Bit of a tangent, but reading this was really interesting in the context of the book I'm reading now, "Ra."[1]

It takes place in a modern day world where "magic" was discovered decades ago and is now a formal science with graduate programs right up there with engineering and physics. It has rules, and in fact one character just created a magical quine (which was apparently thought to be impossible).

If every sufficiently advanced technology is indistinguishable from magic, I wonder what the turning point was when people stopped thinking of electricity as magic and instead thought of it as science.

When you get into talk about electrons, how they flow, how they transfer between atoms, and how we end up harnessing them, it is very easy for the D&D nerd in me to mentally replace "electrons" with "mana".

Absolutely fascinating world we live in.

[1] http://qntm.org/ra

Re: What is Electricity?

#25

Post by emcrazyone »

Couldn't read much past the statement:

"Electricity is briefly defined as the flow of electric charge, but there’s so much behind that simple statement"

Electricity is the force not the flow. The flow is the current. The term, "Electricity" in every college course I had on it in getting my degrees is always the EMF (Electromotive Force).

Sorry to nit pick but I just have a real problem when articles are written from sense of authority (An electronics company) and don't get the details correct. It can kick off a cycle of incorrect learning and confusion if you're relatively new and getting into electronics.

Re: What is Electricity?

#27

Post by jimmahoney »

I like Dave Barry's explanation of electricity (e.g. http://www.comp.leeds.ac.uk/Perl/Misc/electricity.txt ) including

"the electric company sends electricity through a wire to a customer, then immediately gets the electricity back through another wire, then (this is the brilliant part) sends it right back to the customer again. This means that an electric company can sell a customer the same batch of electricity thousands of times a day and never get caught, since very few customers take the time to examine their electricity closely. In fact, the last year any new electricity was generated was 1937."

and

"AMAZING ELECTRONIC FACT: If you scuffed your feet long enough without touching anything, you would build up so many electrons that your finger would explode! But this is nothing to worry about unless you have carpeting."

Re: What is Electricity?

#28

Post by agumonkey »

jimmahoney wrote: post #27

I like Dave Barry's explanation of electricity (e.g. http://www.comp.leeds.ac.uk/Perl/Misc/electricity.txt ) including "the electric company sends electricity through a wire to a customer, then immediately gets the electricity back through another wire, then (this is the brilliant part) sends it right back to the customer again. This means that an electric company can sell a customer the same batch of electricity tho…

Funny Lagrangian view on natural elements property. Even the other businesses are just selling combinatorics.

ps: really nice kind of humor running in this article, love it

``` you picked up batches of "electrons", which are very small objects that carpet manufacturers weave into carpet so that they will attract dirt you picked up batches of "electrons", which are very small objects that carpet manufacturers weave into carpet so that they will attract dirt ```

Re: What is Electricity?

#29

Post by SunSparc »

shostack wrote: post #24

Bit of a tangent, but reading this was really interesting in the context of the book I'm reading now, "Ra."[1] It takes place in a modern day world where "magic" was discovered decades ago and is now a formal science with graduate programs right up there with engineering and physics. It has rules, and in fact one character just created a magical quine (which was apparently thought to be impossible). If every sufficie…

So true. If the Egyptians could see what we play with every day, they would be amazed. I imagine there is quite a bit of shock for people in deep jungle/desert tribes that still live in huts when they are introduced to "modern" technology. Magic is probably the best way for them to explain it initially. Of course, "magic", usually just means, "something I do not understand".

Re: What is Electricity?

#30

Post by SunSparc »

jimmahoney wrote: post #27

I like Dave Barry's explanation of electricity (e.g. http://www.comp.leeds.ac.uk/Perl/Misc/electricity.txt ) including "the electric company sends electricity through a wire to a customer, then immediately gets the electricity back through another wire, then (this is the brilliant part) sends it right back to the customer again. This means that an electric company can sell a customer the same batch of electricity tho…

Great read! Thanks for that.
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