1. What is Electrical Power?

Electrical power is the rate at which electrical energy is transferred by an electric circuit. It's measured in watts (W) and represents how much work can be done by the electrical current.

2. How Does the Calculator Work?

The calculator uses these equations:

Where:

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

Explanation: For DC circuits, power is simply voltage times current. For AC circuits, the power factor accounts for phase difference between voltage and current.

3. Importance of Power Calculation

Details: Calculating electrical power is essential for circuit design, energy consumption estimation, selecting appropriate components, and ensuring electrical safety.

4. Using the Calculator

Tips: Select current type (AC or DC), enter voltage in volts, current in amperes. For AC circuits, specify power factor (default is 1 for resistive loads).

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between AC and DC power?
A: DC power is constant, while AC power oscillates. AC calculations require power factor to account for phase differences.

Q2: What is power factor?
A: Power factor is the ratio of real power to apparent power in AC circuits, ranging from 0 to 1. It represents how effectively current is being converted into useful work.

Q3: When can I assume power factor = 1?
A: For purely resistive loads (like incandescent lights or heaters), power factor is 1. For inductive loads (motors, transformers), it's typically less than 1.

Q4: How does power relate to energy?
A: Energy is power multiplied by time. For example, 100W for 10 hours = 1kWh (kilowatt-hour) of energy.

Q5: What about three-phase power?
A: Three-phase power has a different calculation (P = √3 × V × I × PF). This calculator is for single-phase systems.