ohms law Q
 

confused about ohms law- but let's try to keep this in laymans terms

im debating with a friend right now:

okay ohms law says something like more voltage = more current kinda set up which would mean more power, right?
so im thinking voltage is like pressure pusshing the current... which would = more power...
my friend says that current is based solely on resistence that it's pretty much the less resistance the more power...

this is the way he thinks...
bigger pipe more water flow.. smaller pipe less water flow

the way im thinking...
although it's a bigger pipe, in order for more water to flow you'll need more pressure pushing the water for it to be efficient...

any input?

I=E/R so if resistance goes down (bigger pipe) Current flow will go up if resistance stays the same.

And power=I*E so if current goes up power goes up if the voltage stays the same


***I=current E=voltage R=resistance

:bowdown:


:chuckles: just remembering why I had to cheat in physics class.

Re: ohms law Q
 

power also = I squared * R.

btw, both of you guys are right. it really depends on what you are holding constant and varying. if you say the load resistance is constant, then increasing current will increase voltage and vice versa. however, as you can see from the mentioned equation, current effects power more than resistance.

the hose analogy is the most famous way of relating electrical properties to mechanical properties.

hose diameter = voltage = potential to allow flow through
water pressure = current = the speed or intensity of the flow
crinks, bends, and inner hose roughness = resistance = how much the flow is resisted due to friction and etc.

you are correct about needing more pressure (current) to drive a load and having a larger or smaller diameter hose(voltage) won't do anything without pressure. however, i wouldn't say this causes more efficiency. efficiency is a function of power loses over power input, which is due to resistance.

this arguement can go in circles cause everything depends on something else. you can argue what is more dependent something is of another tho'

i hope this helps.. :thumbup: