newb: I'm trying, but need this cleared up...

[SklettTheNewb]

I have been messing with CircuiMaker and doing "spice simulations"
I have also been reading from these different sites:
http://www.kpsec.freeuk.com/ohmslaw.htm
http://www.play-hookey.com/digital/ripple_counter.html
http://www.allaboutcircuits.com/vol_1/chpt_2/index.html

I'm slowly getting my head around the current and voltage ideas. I
have encountered a strange situation w/ a spice simulation like this:


LED 680
..--|<-----|___|-----.
| |
| |9V
| ---
| -
| |
|-------------------'
(created by AACircuit v1.28.5 beta 02/06/05 www.tech-chat.de)

if I place the probe before the 680 ohm resistor, I get 9v, if I place
it between the resistor and the LED I get 1.79V and 10.60mA

I'm trying to understand how I got that number, I know that;
V
I = -
R

if I use that formula with my values:
9
- = 0.013
680

- that makes no sense.
I'm missing something VERY basic and simple, but I can't figure it out.


Any help or guidance would be REALLY appreciated at this point.
Thanks,
Steve

 

[SklettTheNewb]

Great answeres all, I was missing the "voltage across the component"
part, I was trying to base everything off of the supply voltage.

This makes sense now, thank you for the great responses.
Take it easy,
Steve