By Ohm’s law I = V / R. So high voltage should mean high current for constant resistance? Right? I am very confused how this works. Please explain
In: Physics
Tesla coils produce very high currents if you short them out. Look at [https://youtu.be/BGD-oSwJv3E?t=828](https://youtu.be/BGD-oSwJv3E?t=828)
A major problem with current and voltage that peek and average is different merriment.
If you for example look at a taser the listing on Wikipedia says [https://en.wikipedia.org/wiki/Taser#Function](https://en.wikipedia.org/wiki/Taser#Function)
>A typical TASER device can operate with a peak voltage of 50 [kilo](https://en.wikipedia.org/wiki/Kilo-)[volts](https://en.wikipedia.org/wiki/Volt) (1200 Volts to the body), an electric current of 1.9 milliamps, at for example 19 100 microsecond pulses per second.[^([35])](https://en.wikipedia.org/wiki/Taser#cite_note-Kroll-35) A supplier quotes a current of 3-4 milliamps.
The voltage and the current do not seem to match Ohm’s law. That is because the voltage is peak voltage and the current is average current. If as listed there is 19 pulses each 100 microseconds long per second the on time is only 19 *100 * 10^-6 = 0.0019 seconds = 1.9 mili seconds on every second.
So if the average current is 1.9 milliamps the current during a pulse is 1.9 *10^-3 /1.9 *10^-3 = 1 amp on average during a pulse. Even in a pulse most of the current is in the beginning.
The power source of a taser is energy stored up in a capacitor or a coil, i am not sure, when the energy is drawn from it the voltage drops. So the taser voltage is not 50 000 volts all the time it is 50 000 volts at the beginning of each pulse.
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