This gave me 0.00816
In the AC->DC power adapter it's written 12v-1amp for the ouput.
0.00816 is 8.16mA isn't? I do not understand why it doesn gave 1 amp?
Hi again,
That's not the way electricity works. The adapter is stamped with 12v, 1 amp, because it
puts out 12v at a maximum of 1 amp...note the word "maiximum". That means it doesnt
always put out 1 amp. With smaller loads it can put out anything under 1 amp.
With heavier loads it may actually go above 1 amp but the voltage usually sags down then too.
The spec's have to be taken the right way, and lots of people think exactly the same thing you
have thought when they read the label...i hear this all the time, so dont feel bad, just keep trying
to understand it and you will soon.
One way of thinking of voltage and current is as follows...
The Voltage is the potential to force Current to flow. The voltage forces current to flow, but the resistance of the circuit
limits just how much current the voltage can actually force. In this way you can have say 12v, but if you have different
resistance in different circuits those circuits will all have different currents flowing because their resistance limited the
current flow. It's a balance of sorts, where V=I*R, and many circuits work mostly based on voltage and they draw
whatever current they need (due to their resistance).
For example, if you have a 12v wall wart and you connect a light load, the current may be only 0.010 amps, but if you
connect a heavy load the current may be as high as 1 amp. If you try to connect a load that is GREATER than 1 amp
however that higher current will draw the voltage down to less than 12v in most cases. What this really means is that
you should use that wall wart with a device that requires 12v but does not draw more than 1 amp of current.
So basically you can start to see that the current depends on the load, and it is really the MAX current that is
stamped on the wall wart, not the current that ALWAYS flows when you use the wall wart.