1. What is the Power Ratio Formula?

The power formula (P = V × I × PF) calculates electrical power in AC circuits, accounting for voltage, current, and power factor. It provides the real power consumed by a circuit in watts.

2. How Does the Calculator Work?

The calculator uses the power formula:

Where:

• \( P \) — Power in watts
• \( V \) — Voltage in volts
• \( I \) — Current in amps
• \( PF \) — Power factor (unitless, between 0 and 1)

Explanation: The formula accounts for both the magnitude of voltage and current and their phase relationship through the power factor.

3. Importance of Power Calculation

Details: Accurate power calculation is crucial for circuit design, energy consumption estimation, and electrical system sizing.

4. Using the Calculator

Tips: Enter voltage in volts, current in amps, and power factor (1 for DC circuits or resistive AC loads). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is power factor?
A: Power factor is the ratio of real power to apparent power, representing how effectively current is being converted into useful work.

Q2: What's the difference between real, apparent, and reactive power?
A: Real power (P) does actual work, apparent power (S) is V×I, and reactive power (Q) is the non-working power in inductive/capacitive loads.

Q3: When should I use power factor = 1?
A: For DC circuits or purely resistive AC loads where voltage and current are in phase.

Q4: How does power factor affect energy consumption?
A: Lower power factor means more current is required to deliver the same real power, increasing energy losses in distribution systems.

Q5: What are typical power factor values?
A: Residential: 0.95-1.0, Industrial: 0.8-0.9, Motors at full load: ~0.85, Fluorescent lights: ~0.5-0.9.