1. What is the Electrical Power Formula?

The electrical power formula (P = V × I) calculates the power in watts by multiplying voltage (in volts) by current (in amperes). This fundamental equation is used in electrical engineering and physics to determine the rate of energy transfer in electrical circuits.

2. How Does the Calculator Work?

The calculator uses the power equation:

Where:

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

Explanation: The formula shows that power is directly proportional to both voltage and current. Doubling either voltage or current will double the power output.

3. Importance of Power Calculation

Details: Calculating electrical power is essential for designing circuits, selecting appropriate components, determining energy consumption, and ensuring electrical safety in both residential and industrial applications.

4. Using the Calculator

Tips: Enter voltage in volts and current in amperes. Both values must be positive numbers. The calculator will compute the power in watts.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between AC and DC power calculations?
A: For DC circuits, P = V × I directly. For AC circuits, you need to consider power factor (P = V × I × PF) for accurate calculations.

Q2: How does power relate to energy?
A: Power is the rate of energy transfer. Energy (in watt-hours) = Power (in watts) × Time (in hours).

Q3: What are typical household appliance power ratings?
A: LED bulb: 5-15W, Laptop: 50W, Refrigerator: 100-200W, Microwave: 700-1200W, Hair dryer: 1500W.

Q4: How can I calculate current from power and voltage?
A: Rearrange the formula: I = P / V. Useful for determining circuit breaker requirements.

Q5: What's the relationship between watts and other power units?
A: 1 kW = 1000W, 1 HP ≈ 746W. For apparent power in AC: 1 VA = 1W when power factor is 1.