1. What is Resistor Wattage?

Resistor wattage refers to the maximum amount of power a resistor can safely dissipate without being damaged. It's crucial to select resistors with appropriate wattage ratings for your circuit to prevent overheating and failure.

2. How Does the Calculator Work?

The calculator uses the power formula:

Where:

• \( P \) — Power in watts (W)
• \( I \) — Current through the resistor in amperes (A)
• \( R \) — Resistance in ohms (Ω)

Explanation: The power dissipated by a resistor is proportional to the square of the current flowing through it and its resistance value.

3. Importance of Power Calculation

Details: Calculating resistor wattage is essential for circuit design to ensure components operate within their thermal limits and maintain reliability over time.

4. Using the Calculator

Tips: Enter current in amperes and resistance in ohms. All values must be positive numbers. The calculator will determine the power dissipation in watts.

5. Frequently Asked Questions (FAQ)

Q1: What happens if I exceed a resistor's wattage rating?
A: The resistor may overheat, potentially causing failure, fire hazard, or circuit malfunction.

Q2: How do I choose an appropriate resistor wattage?
A: Select a resistor with at least 2x the calculated power dissipation for safety margin.

Q3: Are there other power formulas for resistors?
A: Yes, you can also use P = V×I or P = V²/R if you know voltage instead of current.

Q4: Why does power increase with the square of current?
A: Because both voltage drop across the resistor (V=I×R) and power (P=V×I) depend on current.

Q5: What about AC circuits?
A: For AC, use RMS current values in the calculation for accurate power dissipation.