1. What is a Length Of Wire Calculator?

Definition: This calculator determines the length of wire based on its electrical resistance, cross-sectional area, and material resistivity.

Purpose: It helps electricians, engineers, and students calculate wire lengths needed for specific electrical properties.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( L \) — Length of wire (meters)
• \( R \) — Electrical resistance (ohms)
• \( A \) — Cross-sectional area (square meters)
• \( \rho \) — Resistivity of material (ohm*meters)

Explanation: The resistance multiplied by area gives the numerator, which when divided by resistivity yields the wire length.

3. Importance of Wire Length Calculation

Details: Accurate wire length calculations ensure proper electrical performance, voltage drop management, and material cost estimation.

4. Using the Calculator

Tips: Enter the resistance in ohms, cross-sectional area in m² (1 mm² = 1e-6 m²), and resistivity (default 1.68×10⁻⁸ for copper). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is resistivity?
A: Resistivity is a material property that quantifies how strongly it opposes electric current (copper = 1.68×10⁻⁸ Ω·m).

Q2: How do I find cross-sectional area?
A: For round wires: A = πr² where r is radius in meters. For AWG wires, consult wire gauge tables.

Q3: What's the resistivity of common materials?
A: Copper = 1.68×10⁻⁸, Aluminum = 2.65×10⁻⁸, Silver = 1.59×10⁻⁸ Ω·m.

Q4: Can I use this for AC circuits?
A: Yes, but for high frequencies consider skin effect which changes effective resistance.

Q5: How accurate is this calculation?
A: It's theoretically accurate for uniform wires at constant temperature. Real-world factors may require adjustments.