1. What is the Power Equation?

The power equation (P = V × I) is a fundamental formula in electrical engineering that calculates the power in watts from voltage and current. It's part of Ohm's Law and is essential for understanding 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 designing electrical circuits, selecting appropriate wire sizes, choosing circuit breakers, and determining energy consumption.

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: For DC circuits and purely resistive AC loads, watts and volt-amps are equal. For reactive loads, they differ due to power factor.

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 1000 watt-hours (1 kWh).

Q3: Can I calculate current if I know power and voltage?
A: Yes, rearrange the formula: \( I = P / V \).

Q4: What are typical household voltages?
A: In North America, 120V for most outlets and 240V for large appliances. Europe uses 230V.

Q5: How do I convert watts to horsepower?
A: 1 horsepower ≈ 746 watts. Divide watts by 746 to get horsepower.