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Resistance Formula:
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The Resistance From Resistivity formula calculates the electrical resistance of a material based on its intrinsic resistivity and physical dimensions. This fundamental relationship helps determine how much a material opposes electric current flow.
The calculator uses the resistance formula:
Where:
Explanation: The formula shows that resistance increases with length and decreases with cross-sectional area, while being directly proportional to the material's resistivity.
Details: Accurate resistance calculation is crucial for designing electrical circuits, selecting appropriate wire sizes, calculating power losses, and ensuring electrical safety in various applications.
Tips: Enter resistivity in Ω·m, length in meters, and cross-sectional area in m². All values must be positive numbers greater than zero for accurate calculation.
Q1: What is resistivity?
A: Resistivity is an intrinsic property of materials that quantifies how strongly they oppose electric current flow, independent of shape or size.
Q2: How does temperature affect resistance?
A: For most conductors, resistance increases with temperature due to increased atomic vibrations that impede electron flow.
Q3: What are typical resistivity values?
A: Copper: 1.68×10⁻⁸ Ω·m, Aluminum: 2.82×10⁻⁸ Ω·m, Silver: 1.59×10⁻⁸ Ω·m, Glass: 10¹⁰-10¹⁴ Ω·m.
Q4: Why does resistance increase with length?
A: Longer conductors provide more obstacles for electrons to navigate, increasing the total opposition to current flow.
Q5: How does cross-sectional area affect resistance?
A: Larger cross-sectional areas provide more pathways for electrons to flow, reducing overall resistance proportionally.