π Definition of Conductivity
Conductivity is a measure of a material's ability to conduct electric current. High conductivity means the material allows current to flow easily. Think of metals like copper and silver β they're excellent conductors! The symbol for conductivity is $\sigma$ (sigma).
π¬ Definition of Resistivity
Resistivity, on the other hand, is a measure of a material's opposition to the flow of electric current. High resistivity means the material resists the current. Think of rubber or glass β they're excellent insulators. The symbol for resistivity is $\rho$ (rho).
π Conductivity vs. Resistivity: A Detailed Comparison
| Feature |
Conductivity ($\sigma$) |
Resistivity ($\rho$) |
| Definition |
β‘ Ability to conduct electric current |
π« Opposition to electric current flow |
| Symbol |
$\sigma$ |
$\rho$ |
| Units |
Siemens per meter (S/m) |
Ohm-meter (Ξ©β
m) |
| Relationship |
Inverse of resistivity: $\sigma = \frac{1}{\rho}$ |
Inverse of conductivity: $\rho = \frac{1}{\sigma}$ |
| Good Conductors |
High conductivity |
Low resistivity |
| Good Insulators |
Low conductivity |
High resistivity |
| Temperature Dependence (Metals) |
Decreases with increasing temperature |
Increases with increasing temperature |
β¨ Key Takeaways
- π‘ Inverse Relationship: Conductivity and resistivity are inversely related. If one is high, the other is low.
- π‘οΈ Temperature Effects: For most metals, conductivity decreases as temperature increases, while resistivity increases.
- π§ͺ Material Properties: These properties are intrinsic to the material and help determine its suitability for various electrical applications.