Recent content by potatocar

So it's only because the same voltage supply is used for different "things" (that require different currents to flow through them)? Do you mean if R<1? So.. a resistor can increase the current?

I don't understand why we use resistors at all. I've read that they cause a voltage drop and decrease the flow of electrons (current). Why is this useful? If we want to decrease the current, why not just lower the voltage? Don't resistors just waste energy?

This is from an older thread: If that's true, how does the electron's spin cause it to behave like a small bar magnet? Why does relativity demand an electron have a magnetic field? Thanks!

1. Probably a stupid question, but what are the +'s? Are they just representing the fact that there is a lack of electrons on that plate, or are those actually some positively charged particles that rearrange themselves like that? 2. Do they actually rearrange themselves like that? Does the...

Homework Statement A=0,078m l=2,27m relative error of A: 0,01 relative error of l: 0,005 What is the error of: arctan(A/l)?

Okay, so let's say there's a rocket traveling upwards, and suddenly a door at the bottom of the rocket opens, and mass starts falling out (not being thrown or pushed out), without touching the rocket (it was all stacked on top of the bottom doors). The rocket doesn't have to gain momentum in...

But if the force which pushes the top object off is parallel, how does it affect the bottom object? It doesn't "push" off of it.

Some silly questions I've just never been able to figure out, and it really bothers me when I don't know if something is a concept like speed, or just a way of describing something else and not in itself tangible. If anyone could take the time to clear these (or some of them) up for me, it would...