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Wire Length Equation:
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The wire length equation calculates the length of a wire based on its electrical resistance, cross-sectional area, and material resistivity. This is fundamental in electrical engineering and physics for designing circuits and selecting appropriate wire gauges.
The calculator uses the wire length equation:
Where:
Explanation: The equation relates the physical dimensions of a wire to its electrical properties, showing how resistance increases with length and decreases with cross-sectional area.
Details: Accurate wire length calculation is crucial for circuit design, power distribution systems, and ensuring proper voltage drop across electrical installations.
Tips: Enter resistance in ohms, area in square meters, and resistivity in ohm-meters. All values must be positive numbers. For common materials, resistivity values are: Copper (1.68×10⁻⁸), Aluminum (2.65×10⁻⁸), Gold (2.44×10⁻⁸) Ω·m.
Q1: Why does wire length affect resistance?
A: Longer wires have more atomic obstacles for electrons to navigate, increasing resistance proportionally with length.
Q2: How does wire diameter affect the calculation?
A: Diameter affects cross-sectional area (Area = πr²). Larger diameter means lower resistance for a given length.
Q3: What is typical resistivity for common materials?
A: Copper: 1.68×10⁻⁸ Ω·m, Aluminum: 2.65×10⁻⁸ Ω·m, Silver: 1.59×10⁻⁸ Ω·m (all at 20°C).
Q4: Does temperature affect the calculation?
A: Yes, resistivity changes with temperature. The calculator assumes standard temperature (usually 20°C).
Q5: How accurate is this calculation for real-world applications?
A: It provides theoretical values. Actual installations may vary due to temperature, impurities, and wire stranding.