The Post Your Thoughts of the Moment Thread 2

[daj]

Yup, I did that, I was just unsure of the step where you divide something by infinity, since I didn't think it was proper. We didn't go over this in class, either, since we're squeezing a course that usually takes an entire school year into 5 weeks.

Erm, tiny little bit of input from my end to this, if you don't mind ^^

The way I was taught it, you shouldn't really need to divide by infinity in your workings, because as you said, it's conceptually incorrect. Kinda. Lots of weird math-y stuff that I don't get either.

But the idea of bringing a point charge to "infinity" actually is derived from the definition of "electric potential energy"; as I recall, it's defined as the "work done to bring a positive test charge from infinity to that point". "Infinity" exists as a point in space where there is no influence from electric fields, and thus potential energy is zero.

It's one of those "wtf" concepts haha, maybe I can draw a graph and send it to you in a pm if you don't get it, it's kinda hard to explain in words ^^;

But anyway to answer your question, the work done to bring a charge from a point to infinity is simply the negative value of the potential energy at that point. Based on the definition of electric potential energy

Hope this helps!

p.s. as an aside i illustrated this using electric potential, but gravity is pretty similar. so same things apply.

[WaluigiTime64]

I can accept it when they're all looking at a topic or board, but now this is just ridiculous.

[Tobbeh99]

Most calm day at work, so far. Really chill.

I usually have to work pretty quickly and fill up to like 7-8 bags, today it was only 3-4 bags! lol.

[Sebastian]

Spoiler

[close]

I can accept it when they're all looking at a topic or board, but now this is just ridiculous.

I'm wondering if they're all the same IP. Maybe it's a glitch.

[InsigTurtle]

Erm, tiny little bit of input from my end to this, if you don't mind ^^

Yeah, I remembered how it was all measured relative to infinity, and how you're technically supposed to say that E approaches 0 as r approaches infinity. But I was pressed for time, so I just scribbled down the 1/infinity and I hoped my teacher wouldn't notice.

Honestly, I think the electromagnetism and special relativity units are more difficult compared to the previous chapters we did that were on classical mechanics, since I've never learned this before. That, and the time constraint we have, are making it pretty stressful, honestly.

[Zunawe]

Electricity and magnetism are the most fun physics I've taken. Quantum mechanics was by far the coolest though.

[mikey]

I'm going to type
in haikus for a while
it seems like fun... yo

[BlackDragonSlayer]

Hey! That's my shtick bub!
You had better be prepared,
For a haiku-off!

[braix]

hippopotamus

oh wait a second

[mikey]

Planned Parenthood is
kind of in real big trouble
copyright issues

[FireArrow]

Wait I'm confused. Are sheilds copywrited by the LDS church or is there more going on?

[EFitTrainr]

I really don't know
And I really do not care.
It's snowing on Mt. Fuji.

[Nitro Indigo]

On a completely unrelated note, according to TV Tropes, The Legendary Starfy on DS killed the franchise because it sold poorly because it averted American Kirby is Hardcore. Last night, I realized that Klonoa: Door to Phantomile on Wii also killed its franchise, and also averted American Kirby is Hardcore (unlike every other Klonoa game released in North America...) - the boxart is exactly the same in every region save for the saturation of the colours. Oh dear.

[Dudeman]

It's snowing on Mt. Fuji.

Eyyyyyyyyyyyyyyyyyyy

[Nitro Indigo]

I had to look that up. (I know what it's a reference to, by the way.)