Physics calculator
Ohm's Law Calculator
Calculate resistance and power from voltage and current.
FormulaResistance = voltage / current; power = voltage x current
Formula
Ohm's law
Electrical calculations can involve safety risks. Verify wiring, ratings, and codes before practical work.
Resistance = voltage / current; power = voltage x current
12 V and 2 A gives 6 ohms and 24 W.
FAQ6 common questions for this calculator.
FAQs
What if current is zero?+
Resistance cannot be calculated from voltage divided by zero, so the calculator protects against that input.
Does this replace circuit design?+
No. It is a basic Ohm's law estimate for simple DC-style calculations.
How does the Ohm's Law Calculator calculate the result?+
For the Ohm's Law Calculator, it uses the Ohm's law: Resistance = voltage / current; power = voltage x current. 12 V and 2 A gives 6 ohms and 24 W.
What information do I need to use the Ohm's Law Calculator?+
For the Ohm's Law Calculator, enter voltage and current. Keep the units consistent with the calculator fields and compare your setup with the worked example on the page.
How accurate is the Ohm's Law Calculator?+
Ohm's Law Calculator is accurate for the quantities and units entered into Ohm's law. Real systems may differ when friction, losses, directions, uncertainty, or non-ideal conditions are relevant.
What should I check before using the Ohm's Law Calculator result?+
For the Ohm's Law Calculator, check voltage and current, unit system, signs or directions, and whether the real situation matches the Ohm's law and worked example. Idealized formulas may not include friction, losses, or uncertainty.
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How to use the Ohm's Law Calculator
Calculate resistance and power from voltage and current. The page also explains the ohm's law and shows a practical example: 12 V and 2 A gives 6 ohms and 24 W.
- 1
Enter your details
Enter voltage and current, then complete any other fields shown in the calculator.
- 2
Check the calculation
Review the result alongside the ohm's law: Resistance = voltage / current; power = voltage x current.
- 3
Compare scenarios
Change one or more inputs to see how they affect the ohm's Law Calculator result before you use the estimate.