1. What is the Power Equation?

The power equation (P = V × I) is a fundamental formula in electrical engineering that calculates 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 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 many watts is 120V at 15A?
A: 120V × 15A = 1800W (1.8 kW). This is the maximum power for a standard 15A household circuit.

Q3: Can I calculate watts with resistance instead of current?
A: Yes, using P = V²/R where R is resistance in ohms.

Q4: Why is power important for electrical safety?
A: Excessive power can cause overheating. Knowing power helps select properly rated wires, fuses, and circuit breakers.

Q5: How does this relate to energy consumption?
A: Energy (kWh) = Power (kW) × Time (hours). Power calculation is the first step in determining energy usage.