So, I've been working on a problem mostly to figure out how heating a cup of coffee works and am kind of lost now. I set up my problem like this. I figured 0.5 L of water would be an okay amount to use and made a fictional simple circuit of a 12 V battery and a resistor with a resistance of R = 0.2 ohms. I'm trying to figure out how long it would take to heat that water a change of 70 K. I'm keeping it simple by not having it go through any phase shifts. The first thing I did was find out how many J of energy it would actually take to raise water 70k. After I did the # crunching (.05 kg * (4190j/kg K)*70K) and came up with a whopping 146,650 J of energy required. This is where I start to get lost though, as I am not that great with circuits. How do I figure out how many joules of heat energy that resistor in that circuit will give off? I know current = Potential V / Resistance. but I don't really know if that applies here....Any ideas on how I can figure out how to find out how many J's of energy the resistor in this circuit gives off a minute if it were placed in the water?