What does electrical resistivity measure?

Electrical resistivity is a fundamental property that quantifies how strongly a given material opposes the flow of electric current. It is a crucial parameter in electrical engineering and material science, indicating how easily electrons can move through a substance. The lower the resistivity, the better the material is at conducting electricity. Materials with high resistivity, on the other hand, are poor conductors and are often used as insulators.

To elaborate, when a voltage is applied across a material, its resistivity dictates how much current will pass through it. For example, metals such as copper and aluminum have low resistivity, making them excellent conductors, while rubber and glass have high resistivity, serving effectively as insulators.

Understanding electrical resistivity is essential for designing circuits, selecting materials for specific applications, and ensuring the safety and efficiency of electrical systems.