1. The problem statement, all variables and given/known data In a domestic house, the voltage on the supply is 230V at angle 0 degrees. A number of household appliances are connected to the single phase supply causing a current of 20A at a power factor of 0.75 lagging to flow from the supply a) What power is being consumed by the loads. b) If energy is charged at 13 cents /KWh, how much would it cost to run the house for 24 hours? c) If an electric radiator(resistive load) drawing 10A were connected in parallel with other loads, what total current would be drawn from the supply? 2. Relevant equations Do I use Average Power = (Vrms)^2 /R. Thing is I dont know what Vrms is? There is also P = Irms X Vrms cos (phi). I think cos phi = power factor = 0.75? 3. The attempt at a solution So is the answer just P = 20 X 230 X 0.75? Also what if the angle was greater than 0 degrees? Does that matter i,e do I have to use a different equation. Thanks, this is really hard, so many equations to remember. ill stick to DC circuit analysis any time of the day!