1. What is the Power Equation?

The power equation P = V² / R calculates electrical power in watts from voltage and resistance. This fundamental formula in electrical engineering relates voltage, resistance, and power in a circuit.

2. How Does the Calculator Work?

The calculator uses the power equation:

Where:

• \( P \) — Power (watts)
• \( V \) — Voltage (volts)
• \( R \) — Resistance (ohms)

Explanation: The equation shows that power is proportional to the square of the voltage and inversely proportional to the resistance in the circuit.

3. Importance of Power Calculation

Details: Accurate power calculation is crucial for circuit design, component selection, energy efficiency analysis, and ensuring electrical safety in various applications.

4. Using the Calculator

Tips: Enter voltage in volts and resistance in ohms. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is the relationship between power, voltage and resistance?
A: Power increases with the square of voltage and decreases as resistance increases, following the formula P = V²/R.

Q2: What are typical power values in electrical circuits?
A: Power values vary widely from milliwatts in small electronic devices to kilowatts in industrial equipment and megawatts in power generation systems.

Q3: When should I use this calculation?
A: Use this calculation when designing electrical circuits, selecting appropriate components, calculating energy consumption, or troubleshooting electrical systems.

Q4: Are there limitations to this equation?
A: This equation applies to DC circuits and AC circuits with purely resistive loads. For reactive loads (inductive or capacitive), additional factors must be considered.

Q5: How does this relate to other power formulas?
A: This is one of three fundamental power formulas. The others are P = I²R (using current) and P = VI (using both voltage and current).