h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I was always taught that voltage was a potential energy difference, nothing to do with pressure.

Hi

you are technically correct, but i was using pressure as a simple explanation to those who have little knowledge of electricity. I know I would find it easier to understand pressure, which it loosey is, than potential difference. To bridge the gap if you have a potential difference, or voltage, and go back to Ohm's law you find if you double the voltage over the same load (resistance) you double the current. So to put it fluidic, and more understandable, terms if you double the pressure through a pipe, then the flow doudles.

It should also be understood that potential difference is the voltage differnce between one voltage and another, usually accross a device, such as a resistor. A 'voltage' usually refers to a voltage source, such as a battery. however a voltage is also a potential differnece, as i'm sure you realise.

also that article was written ages ago and i have now, quite worryingly, forgotten most of first priciples and moved on to other things that i am trying to make a career out of, such as embedded systems.

i hope this has cleared some stuff up and please don't heckle me if i am completely off the mark here, as I said I wrote that ages ago. Your best go and check it out from a book if your still concerned I'm talking rubbish (which i might well be). Aparantly there's quite a good one by a couple of blokes called Horrowitz and Hill.

right i'm off to forget how to remember

MOL