To reference the amperage example above, both the 120-volt circuit with a 10-amp current and the 240-volt circuit with a 5-amp current produce 1200 watts of power.

When you look at the Ohm’s Law Wheel, select this formula: I = W/E (amps = watts ÷ volts); I = 5,000 watts ÷ by 240 volts; I = 20.8 amps; Because the electric space heater on a continuous load ...