1. What is Wattage Calculator from Voltage and Resistance?

Definition: This calculator determines the electrical power (wattage) based on voltage and resistance using Ohm's Law.

Purpose: It helps electricians, engineers, and electronics enthusiasts calculate power dissipation in electrical circuits.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

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

Explanation: The voltage is squared and then divided by the resistance to calculate the power dissipation in the circuit.

3. Importance of Power Calculation

Details: Proper power calculation ensures components are not overloaded, helps design efficient circuits, and prevents overheating.

4. Using the Calculator

Tips: Enter the voltage in volts and resistance in ohms. Resistance must be greater than 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is resistance squared in the formula?
A: Actually, voltage is squared (V²). This comes from combining Ohm's Law (V=IR) with the power formula (P=VI).

Q2: What's a typical resistance value?
A: Resistance varies widely depending on the component - from milliohms in wires to megaohms in insulators.

Q3: Can I use this for AC circuits?
A: Yes, but use RMS voltage values for AC circuits to get accurate power calculations.

Q4: What if I know current instead of voltage?
A: Use P = I²R if you know current and resistance, or P = VI if you know voltage and current.

Q5: Why does resistance need to be greater than zero?
A: Division by zero is undefined, and in practice, all real components have some resistance.