If your going to be doing anything with electronics, Ohms
law is one of the most important things you can learn. In school, Ohms law is gone
over and it is always boring as hell. For that reason I think is why most installers don't
pay much attention to Ohms Law. I print the Ohms Law chart below and post it in the
installation bay and whenever I can I will point out to the installer trainees why
whatever task they are doing while installing relates to the chart. Forinstance, to figure
out how much power an amplifier is delivering to a speaker you can simply measure the
voltage at the speaker terminals and follow the equation. voltage times voltage divided by
the impedance of the speaker, so if you measured 10 volts and had it paying a 4 ohm
speaker the wattage would be 25watts. Simple!!! You can also use the chart to help
you with current draw, wire sizes, and about anything else electrical while installing.
PRINT IT, HANG IT, USE IT! you will be surprised how much
sense it makes!