1. What is Power Calculation?

Power calculation in electrical engineering refers to determining the rate at which electrical energy is transferred by an electric circuit. The basic formula P = V × I calculates electrical power from voltage and current.

2. How Does the Calculator Work?

The calculator uses the fundamental power formula:

Where:

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

Explanation: This formula represents the basic relationship in electrical circuits where power equals the product of voltage and current.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for circuit design, electrical safety, energy consumption analysis, component selection, and determining the capacity requirements for electrical systems.

4. Using the Calculator

Tips: Enter voltage in volts (V) and current in amperes (A). 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 is straightforward. For AC circuits, power factor must be considered: P = V × I × PF for single-phase systems.

Q2: What are typical power values for household appliances?
A: LED bulbs: 5-20W, Laptop: 50-100W, Refrigerator: 100-400W, Microwave: 800-1500W, Electric heater: 1500-3000W.

Q3: How is power related to energy consumption?
A: Energy (kWh) = Power (kW) × Time (hours). Power is the rate of energy consumption, while energy is the total consumption over time.

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

Q5: What safety considerations are important for power calculations?
A: Always ensure components can handle calculated power levels, consider derating for safety margins, and account for power factor in AC systems to prevent overloading.