1. The problem statement, all variables and given/known data So we are doing an experiment where we are trying to place a 60W light bulb in a room. It is connected to the mains power supply, but we are imagining that it is DC instead of AC. Now we have to make sure that we only loose 0.1% of power in the wires. 2. Relevant equations P=VI V=IR R=αL/A 3. The attempt at a solution So if the bulb draws 99.9% of the power I calculated that the remaining one percent is about 0.06W. This is how much we can afford to loose in the wire. Now we can use derived form of the Power equation P=I^2R or P=V^2/R to find R. But I noticed you'd need I or V and I'm not sure what value to use pleases help.