P=V*I applied on DC resistor circuits.

be80be:

Yeah but 12 Ohms is little more than a dead short....

Yep and could look like a glowing heater if you used the right wire, or put it in a bulb and make some light.

I've seen those big resistors bolted to metal plates and to heat them up (eg. in 3D printers where they want the base plate to be hot).