Engineering

Ohm's law

Enter any two of voltage, current and resistance to find the third, plus the power.

Inputs

Leave the value you want to find blank.

Result

Current

24
Voltage
12
Resistance
0.5
Power
288

How it’s calculated

Formula

V=IRV = I R
P=VIP = V I

With your numbers (converted to SI units)

I=12 V0.5 Ω=24 AI = \frac{12\,\text{V}}{0.5\,\Omega} = 24\,\text{A}
P=12 V×24 A=288 WP = 12\,\text{V} \times 24\,\text{A} = 288\,\text{W}

What it means

Voltage pushes current through a resistance. Double the resistance and the current halves at the same voltage. The power is turned into heat in the resistance, which is why high-current wiring has to be thick.

Assumptions

  • A purely resistive (DC) circuit.

Learn the concepts behind this on resources.simbotics.org · All formulas

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