Hello! This is Ross on behalf of expertvillage.com.
Let us talk about current. The sprinkler at the end of your hose works because of water
is flowing through it. In the same way electronic circuits work because electrons are flowing
through it. Nothing is flowing in this circuit yet because the circuit is not complete. It
is not a closed circuit. I am going to apply the power to it from this is power supply
and the LED, lights up. The thing is how much current is it drawing. Well from here we can
see that 2.9 volts is what is being supplied to the circuit. The circuit though itself
demands the current. It calls for current. Current is enforced to it. How much current
is it drawing? 0.01 or 10 milliamps, it is very small. So the biggest thing may be to
get out of this is that current is to determined by the circuit itself. Here is another circuit,
this happens to be just a light bulb. So it is really simple just a filament. It is going
to be the same voltage because I did not adjust it and see how bright it is that brightness
though it is calling for more current we can see same voltage 2.9 volts. The current though
is 0.54 or 540 milliamps much larger it is the circuit that is calling for so as long
as to supply and can meet the demand for the circuit you will get all the current it needs.
The adaptors you are so used to using these that when you pick one out, you have to make
sure the voltage is right and make sure the polarity is right and make sure that it supplies
at least the amount of current that your circuit needs. This one supplies 200 milliamps. Same
thing I could use it on a tape recorder or anything that draws 200 milliamps or less.
This one forced to 200 milliamps to it, but it is able to supply at least that amount.