That is interesting (1 Joule = 1 Watt-second, btw) So, 200 Joules would be 20kW for 1/100 of a second, perhaps. Since chest impedance varies, it would be impossible to set a particular voltage and "shutter speed" as the current would be unpredictible- I'd imagine the defribillator has the "Joule" setting, since the defribillator will automatically adjust the voltage, current and cycle length to administer the proper shock to constrict the heart and get it moving. And thus the voltage and current would never be consistant, and would be meaningless means of measurement. But that's just a guess...
[This message has been edited by SteveFehr (edited 02-21-2007).]
