I have just started learning electronics and I am learning about Ohm's law. I have some simple experiments to do using an LED in series with a resistor. The experiments use a 9V pp3 alkaline battery. I have acquired a lab power supply and want to use the power supply instead of the 9v battery. I just don't know what current to set the power supply to so that I can get the same results as if I used the battery. I would appreciate some concept help please.