1. What is the Power Formula?

The power formula (P = V × I × PF) relates voltage (V), current (I), and power factor (PF) to calculate electrical power (P) in watts. It's fundamental in electrical engineering and circuit analysis.

2. How Does the Calculator Work?

The calculator uses the power formula:

Where:

• \( P \) — Power in watts (W)
• \( V \) — Voltage in volts (V)
• \( I \) — Current in amperes (A)
• \( PF \) — Power factor (unitless, 0 to 1)

Explanation: The formula calculates real power in AC circuits. For DC circuits or purely resistive AC loads, the power factor is 1.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for circuit design, electrical safety, energy efficiency, and proper sizing of electrical components.

4. Using the Calculator

Tips: Enter voltage in volts, current in amps, and power factor (1 for DC circuits). All values must be valid (voltage > 0, current > 0, 0 ≤ PF ≤ 1).

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing phase difference between voltage and current in AC circuits.

Q2: When should I use PF=1?
A: Use PF=1 for DC circuits or purely resistive AC loads (like incandescent lights or heaters).

Q3: What's the difference between real, apparent, and reactive power?
A: Real power (P) does work, apparent power (S) is V×I, reactive power (Q) is stored and released. \( S^2 = P^2 + Q^2 \).

Q4: How does this relate to energy consumption?
A: Energy (kWh) = Power (kW) × Time (hours). This formula helps calculate power which can then be used for energy calculations.

Q5: What are typical power factors?
A: Motors: 0.8-0.9, fluorescent lights: 0.7-0.9, computers: 0.6-0.7, purely resistive loads: 1.0.