I'm new to electronics and such. I was wondering if anyone knew how much current runs from a 9 volt battery? I thought it was one set amount for every battery, but a friend says otherwise. If you can answer this it would be helpful.
Not 100% sure what you mean there.
The current flowing through your circuit
is limited by the resistance of your circuit.
But also the internal resistance of the
battery will prevent too much current flowing.
Any battery can only supply a certain amount
of current over time. 9V (PP3?) is somewhere
around 300milli-amp-hours(best check though!).
So the battery can supply 300mill-amps for 1 hour.