How to Calculate Volt & Amps
- 1). Multiply the electrical power by the resistance, then take the square root of the product to calculate the voltage. For example, if the electrical power is 200 watts and the resistance is 24 ohms, then voltage = sqrt (200 x 24) = 69.28 volts. Note that "sqrt" denotes the square root mathematical operation.
- 2). Divide the electrical power by the resistance, then take the square root of the quotient to calculate the current. For instance, if the electrical power is 90 watts and the resistance is 10 ohms, then current = sqrt (90 / 10) = 3 amperes.
- 3). Multiply the current by the electrical resistance to calculate the voltage. For example, if the current is 2.5 amperes and the resistance is 15 ohms, then the voltage = 2.5 amperes x 15 ohms = 37.5 volts.
- 4). Divide the voltage by the electrical resistance to calculate the electric current. For instance, if the voltage is 45 volts and the resistance is 30 ohms, then the current = 45 volts/30 ohms = 1.5 amperes.
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