1. What is Wire Resistance?

Wire resistance is the opposition to the flow of electric current through a conductor. It depends on the material's resistivity, the length of the wire, and its cross-sectional area according to the formula R = ρL/A.

2. How Does the Calculator Work?

The calculator uses the wire resistance formula:

Where:

• \( R \) — Electrical resistance (Ω)
• \( \rho \) — Resistivity of the material (Ω·m)
• \( L \) — Length of the wire (m)
• \( A \) — Cross-sectional area of the wire (m²)

Explanation: Resistance increases with length and resistivity, but decreases with increasing cross-sectional area.

3. Importance of Resistance Calculation

Details: Calculating wire resistance is essential for electrical circuit design, power transmission systems, and selecting appropriate wire gauges to minimize power loss and prevent overheating.

4. Using the Calculator

Tips: Enter resistivity in Ω·m, length in meters, and cross-sectional area in square meters. All values must be positive numbers greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is typical resistivity for common materials?
A: Copper: 1.68×10⁻⁸ Ω·m, Aluminum: 2.82×10⁻⁸ Ω·m, Silver: 1.59×10⁻⁸ Ω·m, Gold: 2.44×10⁻⁸ Ω·m.

Q2: How does temperature affect resistance?
A: Resistance generally increases with temperature for most conductors due to increased atomic vibrations that impede electron flow.

Q3: Why use square meters for area?
A: The SI unit for area is m². For practical applications, you can convert from mm² (1 mm² = 1×10⁻⁶ m²).

Q4: What is the relationship between resistance and wire gauge?
A: Larger gauge numbers indicate thinner wires with higher resistance, while smaller gauge numbers indicate thicker wires with lower resistance.

Q5: When is this formula not applicable?
A: This formula assumes uniform material properties and cross-section, and may not apply accurately at very high frequencies or for non-ohmic materials.