1. What is the Power Equation?

The power equation (P = V × I) calculates electrical power from voltage and current. It is a fundamental formula in electrical engineering that determines the rate at which electrical energy is transferred by an electric circuit.

2. How Does the Calculator Work?

The calculator uses the power equation:

Where:

• \( P \) — Power in watts
• \( V \) — Voltage in volts
• \( I \) — Current in amperes

Explanation: This equation demonstrates the direct proportional relationship between power, voltage and current in electrical systems.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for circuit design, energy consumption analysis, electrical safety assessments, and determining appropriate component specifications in electrical systems.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between AC and DC power calculation?
A: For DC circuits, P = V × I applies directly. For AC circuits, power factor must be considered: P = V × I × PF.

Q2: How does this relate to energy consumption?
A: Power (watts) multiplied by time (hours) gives energy consumption (watt-hours), which is what utility companies bill for.

Q3: What are typical voltage and current values in household applications?
A: Standard household voltage is 120V or 240V depending on region, with current varying based on appliance power requirements.

Q4: Can this formula be used for three-phase systems?
A: For balanced three-phase systems, the formula becomes P = √3 × V × I × PF, where V is line voltage and I is line current.

Q5: How accurate is this calculation for real-world applications?
A: The formula provides theoretical maximum power. Actual power may be lower due to factors like resistance, efficiency losses, and power factor in AC systems.