Answer:
Divide the voltage running through the cable by your target current. If, for instance, 120 volts will act on the cable, and you want 30 amps to run through it: 120 / 30 = 4. This is your target resistance, measured in ohms.
Multiply the cable's length by its material's resistivity. Copper, for instance, has a resistivity of 1.724 x 10^-8 ohm meters at room temperature. If your cable must measure 30,000 meters in length
Explanation:
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