1. What is the Power Equation?

The power equation P = V × I is a fundamental formula in electrical engineering that calculates the total power in watts. It represents the relationship between voltage (V), current (I), and power (P) in an electrical circuit.

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 demonstrates that power is directly proportional to both voltage and current in an electrical circuit.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for designing electrical systems, determining energy consumption, selecting appropriate components, and ensuring electrical safety in various applications.

4. Using the Calculator

Tips: Enter voltage in volts (V) and current in amperes (A). All values must be valid positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is the difference between AC and DC power calculation?
A: For DC circuits, P = V × I is straightforward. For AC circuits, power factor must be considered: P = V × I × PF, where PF is the power factor.

Q2: How does this relate to energy consumption?
A: Energy consumption is calculated by multiplying power by time: E = P × t, where E is energy in watt-hours and t is time in hours.

Q3: Can this formula be used for three-phase systems?
A: For balanced three-phase systems, the formula is P = √3 × V × I × PF, where V is line voltage and I is line current.

Q4: What are typical voltage and current values in household applications?
A: In North America, standard household voltage is 120V, while in many other regions it's 220-240V. Current varies by appliance from less than 1A to 15A or more.

Q5: How accurate is this calculation for real-world applications?
A: The formula provides theoretical power calculation. In practical applications, factors like resistance, efficiency, and power factor may affect actual power consumption.