1. What is the Power Equation?

The power equation (P = V × I) calculates the power dissipation in watts through a resistor or electrical component when you know the voltage across it and the current flowing through it.

2. How Does the Calculator Work?

The calculator uses the power equation:

Where:

• \( P \) — Power in Watts
• \( V \) — Voltage in Volts
• \( I \) — Current in Amps

Explanation: This fundamental equation in electrical engineering relates the three basic electrical quantities.

3. Importance of Power Calculation

Details: Calculating power dissipation is crucial for selecting properly rated resistors and preventing overheating in electronic circuits.

4. Using the Calculator

Tips: Enter voltage in volts and current in amps. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: Why is power calculation important for resistors?
A: Resistors have maximum power ratings. Exceeding this rating can cause overheating and failure.

Q2: What are typical resistor power ratings?
A: Common ratings include 1/8W, 1/4W, 1/2W, 1W, 2W, 5W, etc. Higher power resistors are physically larger.

Q3: Can I use this for AC circuits?
A: For AC, you need to use RMS values of voltage and current for accurate power calculation.

Q4: What happens if I exceed a resistor's power rating?
A: The resistor may overheat, change value, or fail completely, potentially damaging the circuit.

Q5: Are there other power equations?
A: Yes, power can also be calculated as P = I²R or P = V²/R when resistance is known.