Ohm's Law Calculator

    Provide any two of V, I, R to compute the others and power.

    Inputs

    About Ohm’s Law

    Ohm’s Law is a fundamental electrical principle that defines the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit. It provides a simple yet powerful way to analyze and design electrical systems, helping you predict how voltage and current behave under various conditions.

    •Core Principle

    Ohm’s Law states that the current flowing through a conductor between two points is directly proportional to the voltage across the two points, and inversely proportional to the resistance of the conductor. Mathematically expressed as:

    • –V = I × R — Voltage equals current multiplied by resistance.
    • –I = V ÷ R — Current equals voltage divided by resistance.
    • –R = V ÷ I — Resistance equals voltage divided by current.

    •Features

    • –Explains the linear relationship between voltage, current, and resistance in most conductive materials.
    • –Helps in calculating unknown circuit parameters when two are known (V, I, or R).
    • –Applicable to both DC and AC circuits with resistive components.
    • –Forms the foundation for understanding electrical power, energy loss, and efficiency.

    •How to Use

    1. 1.Enter any two known values (e.g., voltage and current) into the calculator.
    2. 2.The calculator automatically computes the third value (e.g., resistance).
    3. 3.Optionally, include power (P) to find related quantities using P = V × I.
    4. 4.Use the results to design or troubleshoot circuits efficiently.

    •Power Relationship

    • –P = V × I — Power equals voltage multiplied by current.
    • –P = I² × R — Power can also be expressed using current and resistance.
    • –P = V² ÷ R — Power can also be calculated using voltage and resistance.

    These formulas are useful for analyzing energy consumption and efficiency in electrical systems.

    •Practical Applications

    • –Designing and testing resistive circuits in electronics and electrical systems.
    • –Calculating required resistor values for voltage and current control.
    • –Estimating power losses and ensuring components are rated correctly.
    • –Troubleshooting circuits by measuring voltage and current to detect faults.

    •Limitations

    • –Ohm’s Law applies only to materials that maintain a constant resistance (ohmic materials).
    • –It does not accurately describe semiconductors, diodes, or other non-linear components.
    • –Temperature changes can affect resistance, altering real-world results.

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