Electrical conductivity

Definition

Electrical conductivity is a measure of a material's ability to conduct an electric current. It is the reciprocal of electrical resistivity and is denoted by the symbol $\sigma$.

5 Must Know Facts For Your Next Test

1. The SI unit of electrical conductivity is Siemens per meter (S/m).
2. Conductivity depends on the number of free charge carriers in a material.
3. Metals typically have high conductivity due to abundant free electrons.
4. Temperature can affect conductivity; for metals, it usually decreases with increasing temperature.
5. Electrical conductivity is mathematically related to resistivity by $\sigma = \frac{1}{\rho}$, where $\rho$ is resistivity.

Review Questions

• What is the relationship between electrical conductivity and resistivity?
• How does temperature generally affect the electrical conductivity of metals?
• What factors influence the electrical conductivity of a material?

Related terms

Resistivity: A measure of how strongly a material opposes the flow of electric current, denoted by $\rho$.

Ohm's Law: $V = IR$, where $V$ is voltage, $I$ is current, and $R$ is resistance.

Current Density: The amount of electric current flowing per unit area, denoted by $J$ and measured in amperes per square meter (A/m²).