Ok, I'm preparing to get shot down here because maybe this is a really dumb question but here we go... How does an electric current know to supply more energy (joules per second) to higher wattage appliances? For example: At home I can plug a 10W, 50W, 60W or 100W light bulb into a socket and they all work and emit different brightnesses. Why? What is it about the 100W light bulb that makes it draw more power? It is the resistance? If so does it have more or less than a 60W? Iif it has less R then surely it wouldn't get so hot and therefore so bright and if it had more R then, well, I can't understand why that would make it bright either. Have I just asked the most stupid question ever on Physics Forum? If anyone can help me clear this up that would be great. Thanks.