What is Resistivity?
Resistivity is defined as the resistance of a substance per unit length for a unit cross-section. The conductor’s resistivity is only proportional to its temperature. It also depends on the nature of the conductor’s substance. The ohmmeter is the SI unit of resistance. Temperature increases resistivity linearly. In comparison to insulator resistivity, conductor resistivity is low.
Resistivity Formula:
Resistivity (ρ) = Resistance (R) x Cross-sectional area (A) / Length (L)
Note: Several factors influence a material’s resistivity, including its composition, temperature, and contaminants. Insulators, for example, have a larger resistance to the flow of electric current than metals, which have a low resistivity. This is because insulators have fewer free electrons than metals.
Difference Between Resistance And Resistivity
Understanding how electricity travels through materials is crucial in electronics and physics. Resistance and resistivity are key terms often confused, yet they describe different aspects of electrical conduction. Resistance measures how much an object hinders electric current, while resistivity reflects the inherent ability of the material itself to resist current.
This article clarifies the differences between these two fundamental concepts, highlighting their importance and impact on electrical systems.