I understand basically that the current, or amps, are what cause harm, but based on Ohm’s law, V=IR, for the amps to be so low with such high voltage, the resistance must be very high. So why do you need such a high voltage in the first place? Wouldn’t that require a transformer to step up the voltage? And doesn’t such a high voltage create a safety risk, for instance if a conductor with lower resistance came into contact with the voltage source? If you want low amps as not to electrocute animals/people, would it not be easier to use lower voltage?
Just curious and trying to understand. Electricity is like magic to me.
In: Physics
Because generally speaking, of course to a point, voltage isn’t what kills, current does.
Voltage IS what hurts, though. The whole point of electric fences, tasers, batons, etc is to hurt without killing.
Wattage tells you how much electricity there is, simply put.
Wattage is derived from voltage in volts times current in amps.
High voltage power lines of course have lots of current because they have to supply hundreds, thousands, millions of homes. They’re very high wattage overall.
But electric fences don’t really have much of a load, they don’t need much current. Conversely, electric motors like those found on machine tools need relatively low voltage (110, 220, etc are relatively low compared to what’s on an electric fence or on big transmission lines) but need LOTS of current to get the motor to move, sometimes needing a whole circuit in the house dedicated to that one machine.
If you think of electricity like a spring:
Current would be some of the physical properties of the spring. Its material, how big around the spring steel wire is that makes it up, the spacing of coils,
Voltage would be how much that spring is compressed or in tension.
Wattage therefore is derived from those two properties.
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