Quote Originally Posted by richard View Post
yes Charlie the average voltage = 0 and the average current =0 yet the load resistor gets hot . perhaps you have just discovered dark energy
Well, Richard, you did bring up the math. And the mathematical reason we don't use average is that it's no where near correct, in fact the average IS 0. This is a sine function, so calculating the absolute value average is a bit more complicated. You need to integrate the area under the curve as was outlined above. The way you do that is to square all the instantaneous values, take the average, then take the square root of that. For a sine function, that is the peak to peak value * square root of 2 (0.707)