1. What is the Power Equation?

The power equation (P = V × I) is a fundamental formula in electrical engineering that calculates electrical power in watts from voltage and current. It's part of Ohm's Law and is essential for designing and analyzing 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 equation shows that power is directly proportional to both voltage and current. Doubling either voltage or current will double the power.

3. Importance of Power Calculation

Details: Calculating power is crucial for determining energy consumption, sizing electrical components, ensuring circuit safety, and estimating operating costs of electrical devices.

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 watts and volt-amps?
A: Watts represent real power, while volt-amps represent apparent power. They're equal in DC circuits or AC circuits with purely resistive loads.

Q2: How does this relate to energy consumption?
A: Energy (in watt-hours) is power multiplied by time. A 100W device running for 10 hours consumes 1000Wh or 1kWh.

Q3: Can I use this for AC circuits?
A: For AC circuits with purely resistive loads, yes. For reactive loads, you need to consider power factor.

Q4: What's a typical power consumption for household devices?
A: LED bulbs: 5-20W, Laptop: 30-90W, Refrigerator: 100-400W, Microwave: 600-1200W.

Q5: How do I calculate current from power and voltage?
A: Rearrange the formula: I = P / V. For example, a 60W bulb at 120V draws 0.5A.