Ohm's Law Calculator

Calculate voltage, current, resistance, and power using Ohm's Law. Essential for electrical engineering, circuit design, and electronics projects.

Ohm's Law Calculator

Input Parameters

Calculation

Understanding Ohm's Law

Ohm's Law describes the relationship between voltage, current, and resistance in an electrical circuit. It was first formulated by German physicist Georg Ohm in 1827.

Basic Formula

The core Ohm's Law equation is: V = I × R, where V is voltage in volts, I is current in amperes, and R is resistance in ohms.

This formula can be rearranged to solve for any of the three variables:

For voltage: V = I × R

For current: I = V ÷ R

For resistance: R = V ÷ I

Power Calculation

Power (P) in an electrical circuit can be calculated using Ohm's Law:

P = V × I (Power = Voltage × Current)

Using substitution with Ohm's Law, power can also be expressed as:

P = V² ÷ R (Power = Voltage² ÷ Resistance)

P = I² × R (Power = Current² × Resistance)

Practical Applications

Ohm's Law is fundamental in electrical engineering and electronics. It's used for:

  • Circuit design and analysis
  • Selection of appropriate resistors and other components
  • Troubleshooting electrical problems
  • Calculating power consumption

Limitations

While Ohm's Law is a powerful tool, it has some limitations:

  • It doesn't apply to non-linear devices like diodes and transistors
  • Resistance changes with temperature, affecting calculations
  • In AC circuits, the relationship becomes more complex due to reactance and impedance

Frequently Asked Questions

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