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 the three key electrical quantities.

2. How Does the Calculator Work?

The calculator uses the power equation:

Where:

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

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

3. Importance of Power Calculation

Details: Calculating electrical power is essential for circuit design, energy consumption analysis, component sizing, and electrical safety assessments.

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 are the units for power calculation?
A: Power is measured in watts (W), voltage in volts (V), and resistance in ohms (Ω).

Q2: Can this formula be used for AC circuits?
A: This formula applies to DC circuits. For AC circuits, additional factors like power factor must be considered.

Q3: What happens if resistance is zero?
A: Resistance cannot be zero in practical circuits as it would result in infinite current and power, which is physically impossible.

Q4: How does power relate to energy consumption?
A: Power represents the rate of energy consumption. Energy (in watt-hours) is power multiplied by time.

Q5: Are there other power formulas?
A: Yes, power can also be calculated as P = V×I (voltage times current) or P = I²×R (current squared times resistance).