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Resistivity Formula:
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Resistivity is a fundamental property of materials that quantifies how strongly they oppose electric current. Copper has a standard resistivity of 1.68 × 10⁻⁸ Ω·m at 20°C, making it one of the most conductive metals commonly used in electrical applications.
The calculator uses the resistivity formula:
Where:
Explanation: This formula relates the intrinsic property of the material (resistivity) to the measurable electrical resistance of a specific conductor geometry.
Details: Calculating resistivity is essential for material characterization, quality control in manufacturing, designing electrical systems, and selecting appropriate materials for specific applications based on their conductive properties.
Tips: Enter resistance in ohms (Ω), cross-sectional area in square meters (m²), and length in meters (m). All values must be positive. The calculator will compute the resistivity and compare it with the standard value for copper.
Q1: What is the standard resistivity of copper?
A: The standard resistivity of copper at 20°C is 1.68 × 10⁻⁸ Ω·m (0.0000000168 Ω·m).
Q2: Why does copper have low resistivity?
A: Copper has low resistivity due to its atomic structure with free electrons that can move easily through the lattice, making it an excellent conductor.
Q3: How does temperature affect copper resistivity?
A: Resistivity increases with temperature due to increased atomic vibrations that scatter electrons, following the relationship ρ = ρ₀[1 + α(T - T₀)].
Q4: What are common applications of copper based on its resistivity?
A: Electrical wiring, power transmission lines, motors, transformers, printed circuit boards, and various electronic components.
Q5: How does copper resistivity compare to other metals?
A: Copper has the second lowest resistivity among common metals after silver (1.59 × 10⁻⁸ Ω·m), but is more cost-effective for most applications.