Finding the wattage rating of resistors and variable resistors?
Is there a way to find the wattage rating of resistors and such mathematically? or is it something that has to be tested in real life? I have quite a few resistors that I'd like to use, but don't know the wattage rating of them. I only know their resistance, and I could calculate other values if I put voltage across them with a multimeter. Also, what type of variable resistor would you recommend to control a 12 VDC device that draws 12 amps?