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Wire Resistance Formula:
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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. Understanding wire resistance is crucial for electrical engineering and circuit design.
The calculator uses the fundamental wire resistance formula:
Where:
Explanation: Resistance increases with length and decreases with cross-sectional area. Different materials have different resistivity values.
Details: Accurate resistance calculation is essential for proper circuit design, voltage drop calculations, power loss estimation, and selecting appropriate wire gauges for electrical installations.
Tips: Enter resistivity in Ω·m, length in meters, and cross-sectional area in square meters. All values must be positive numbers. Common resistivity values: Copper = 1.68×10⁻⁸ Ω·m, Aluminum = 2.82×10⁻⁸ Ω·m.
Q1: What is resistivity?
A: Resistivity is an intrinsic property of materials that quantifies how strongly they oppose electric current flow. It's measured in ohm-meters (Ω·m).
Q2: How does wire gauge affect resistance?
A: Larger gauge numbers indicate thinner wires with smaller cross-sectional areas, resulting in higher resistance for the same length.
Q3: Why does resistance increase with temperature?
A: For most conductors, atomic vibrations increase with temperature, making it harder for electrons to flow through the material.
Q4: What are common resistivity values?
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.
Q5: How do I calculate cross-sectional area for round wires?
A: For round wires, A = πr² = π(d/2)², where r is radius and d is diameter in meters.