1. What is the Power Formula?

The power formula W = V² / R calculates electrical power in watts from voltage and resistance. This formula is derived from Ohm's law and the basic power equation, providing a direct way to calculate power dissipation in resistive circuits.

2. How Does the Calculator Work?

The calculator uses the power formula:

Where:

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

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

3. Importance of Power Calculation

Details: Calculating power is essential for designing electrical circuits, determining component ratings, ensuring safety, and optimizing energy efficiency in electrical systems.

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 is the relationship between voltage, resistance, and power?
A: Power increases with the square of voltage and decreases as resistance increases, following the formula W = V²/R.

Q2: Can this formula be used for AC circuits?
A: This formula works for DC circuits and AC circuits with purely resistive loads. For reactive loads, additional factors like power factor must be considered.

Q3: What are typical power values in household circuits?
A: Household appliances typically range from a few watts (LED bulbs) to several thousand watts (electric heaters, ovens).

Q4: How does this relate to energy consumption?
A: Power (watts) multiplied by time (hours) gives energy consumption (watt-hours), which is what utility companies bill for.

Q5: Are there safety considerations when working with high power?
A: Yes, high power circuits can generate significant heat and require proper component sizing, cooling, and safety precautions to prevent overheating and fire hazards.