1. What is the AWG Wire Resistance Equation?

The AWG (American Wire Gauge) wire resistance equation calculates the electrical resistance of a wire based on its material properties, length, and cross-sectional area (determined by AWG size). It's fundamental for electrical engineering and circuit design.

2. How Does the Calculator Work?

The calculator uses the wire resistance equation:

Where:

• \( R \) — Resistance in ohms (Ω)
• \( \rho \) — Resistivity of the material (Ω·m)
• \( L \) — Length of the wire (meters)
• \( A_{awg} \) — Cross-sectional area (m²) calculated from AWG size

Explanation: The equation shows that resistance increases with length and resistivity, but decreases with larger cross-sectional area.

3. Importance of Wire Resistance Calculation

Details: Accurate resistance calculation is crucial for proper voltage drop estimation, power loss calculations, and ensuring safe current carrying capacity in electrical systems.

4. Using the Calculator

Tips: Enter resistivity (1.68×10⁻⁸ Ω·m for copper), length in meters, and select AWG size. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the default resistivity value?
A: The default is 1.68×10⁻⁸ Ω·m, which is the resistivity of copper at 20°C.

Q2: How does AWG relate to wire diameter?
A: AWG is a logarithmic scale where higher numbers mean thinner wires. Each 6 AWG decrease doubles the diameter.

Q3: Why does resistance increase with temperature?
A: Most conductors have positive temperature coefficients - as temperature increases, resistivity increases.

Q4: What's the difference between resistance and impedance?
A: Resistance is the DC opposition to current, while impedance includes both resistance and reactance (AC effects).

Q5: How accurate is this calculation?
A: It provides theoretical DC resistance. Actual resistance may vary due to temperature, frequency (skin effect), and manufacturing tolerances.