Ohm's Law Calculator
A fundamental tool for electricians, engineers, and students. Solve for voltage (V), current (A), resistance (Ω), and power (W) by entering any two known values.
Mastering the Fundamentals: Ohm's Law and Power
Ohm's Law is the cornerstone of electrical engineering and electronics. It describes the relationship between three fundamental quantities: voltage, current, and resistance. Understanding this relationship is non-negotiable for anyone studying or working in the electrical field, from residential electricians to industrial engineers. It allows professionals to design circuits, troubleshoot faults, and ensure the safety and efficiency of electrical systems.
The Core Formulas
The beauty of Ohm's Law lies in its simplicity. The relationships can be expressed in three ways:
- Voltage (V) = Current (I) × Resistance (R)
- Current (I) = Voltage (V) / Resistance (R)
- Resistance (R) = Voltage (V) / Current (I)
In addition to these, the electrical power (P), which represents the rate of energy consumption in a circuit, is also directly related. The formula for power is:
- Power (P) = Voltage (V) × Current (I)
This calculator automates these calculations, allowing you to enter any two known values to instantly find the other two. It's a perfect learning aid for our Electrician course students and a handy reference for seasoned professionals.
Practical Use Cases
- Circuit Design: Determine the correct resistor to use in an LED circuit to prevent it from burning out.
- Troubleshooting: If a motor is drawing too much current, an electrician can measure the voltage and resistance to diagnose the problem.
- Power Calculation: Calculate the power consumption of an appliance to select the appropriate wire size and circuit breaker.
- Safety Checks: Ensure that a circuit's resistance is low enough to allow a circuit breaker to trip safely in case of a short circuit.