1. What is the Power Formula?

The power formula P = V² / R calculates electrical power from voltage and resistance. This fundamental equation in electrical engineering helps determine the power dissipated in a resistive component.

2. How Does the Calculator Work?

The calculator uses the power formula:

Where:

• \( P \) — Power in watts (W)
• \( V \) — Voltage in volts (V)
• \( R \) — Resistance in ohms (Ω)

Explanation: The formula shows that power is proportional to the square of the voltage and inversely proportional to the resistance.

3. Importance of Power Calculation

Details: Accurate power calculation is essential for circuit design, component selection, thermal management, and ensuring electrical safety in various applications.

4. Using the Calculator

Tips: Enter voltage in volts and resistance in ohms. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What are the units for power calculation?
A: Power is measured in watts (W), voltage in volts (V), and resistance in ohms (Ω).

Q2: Can this formula be used for AC circuits?
A: This specific formula is primarily for DC circuits. For AC circuits with resistive loads, RMS values should be used.

Q3: What happens if resistance is zero?
A: Resistance cannot be zero in practical circuits as it would result in infinite current and power, which is physically impossible.

Q4: How does power relate to heat dissipation?
A: The calculated power represents the rate at which energy is converted to heat in a resistive component.

Q5: Are there other power formulas?
A: Yes, power can also be calculated using P = V × I (voltage times current) or P = I² × R (current squared times resistance).