1. What is the Power Equation?

The power equation (P = V × I) calculates electrical power in watts from voltage and current. It's a fundamental formula in electrical engineering and physics that relates these three basic 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)
• \( I \) — 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 essential for designing electrical circuits, selecting appropriate wire sizes, determining energy consumption, and ensuring electrical safety.

4. Using the Calculator

Tips: Enter voltage in volts and current in amps. 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 (VA) 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 (watt-hours) is power multiplied by time. A 100W device running for 10 hours consumes 1000Wh (1kWh) of energy.

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

Q4: What's a typical current for household appliances?
A: In 120V systems, a 60W bulb draws 0.5A, while a 1500W heater draws about 12.5A.

Q5: How do I convert watts to amps?
A: Rearrange the formula: I = P / V. For example, 1200W at 120V = 10A.