1. What is the DC Power Equation?

The DC power equation (P = I² × R) calculates the power dissipated in a resistive component in a direct current (DC) circuit. It's one of the fundamental equations in electrical engineering and physics.

2. How Does the Calculator Work?

The calculator uses the DC power equation:

Where:

• \( P \) — Power in watts (W)
• \( I \) — Current in amperes (amps)
• \( R \) — Resistance in ohms (Ω)

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

3. Importance of Power Calculation

Details: Calculating power is essential for circuit design, component selection, and thermal management. It helps determine if components can handle the power without overheating.

4. Using the Calculator

Tips: Enter current in amps and resistance in ohms. Both values must be positive numbers. The calculator will compute the power in watts.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between this and P = V × I?
A: Both calculate power, but P = I² × R is useful when you know current and resistance, while P = V × I is used when you know voltage and current.

Q2: Does this equation work for AC circuits?
A: For AC circuits with purely resistive loads, it works similarly. For reactive loads, you need to consider power factor.

Q3: What happens if resistance is zero?
A: In theory, power would be zero, but in practice, zero resistance (superconductivity) requires special conditions.

Q4: Why is power proportional to current squared?
A: Because both voltage drop across the resistor (V = I×R) and power (P = V×I) depend on current, resulting in P = I²×R.

Q5: How does this relate to heat generation?
A: The calculated power is directly converted to heat in the resistor, which is why power ratings are critical for components.