i have an arduino uno and would like to plug an audio speaker (5W -not 0.5W- 8 ohm).
would anyone have the kindness to tell me what resistor should i use for it? (and explain the calculation behind it so i won't bother again ;P)
as a note i've already checked the "arduino tutorial tone". but got scared trying since the wattage of the speaker wasn't revealed...(or does it make sense or matter?)
Ohm's law isn't difficult...you'll be glad you made the effort to do it on your own.