Conductivity

Definition

Conductivity is a measure of a material's ability to allow the flow of electric charge or current through it. It is an important property that determines how effectively a substance can conduct electricity and is a crucial factor in understanding various electrical phenomena.

5 Must Know Facts For Your Next Test

1. Conductivity is directly proportional to the number and mobility of charge carriers within a material, such as free electrons in metals or ions in electrolytes.
2. Materials with high conductivity, such as metals, allow for the easy flow of electric current, while insulators with low conductivity, like rubber or glass, resist the flow of current.
3. Conductivity is an essential property in understanding the behavior of conductors in electrostatic equilibrium, where charges distribute themselves on the surface of the conductor.
4. The model of conduction in metals, based on the free electron theory, explains how the high conductivity of metals arises from the abundance of freely moving electrons.
5. Ohm's law, which relates current, voltage, and resistance, is a fundamental principle in understanding the flow of electricity and the role of conductivity in electrical circuits.

Review Questions

• Explain how the concept of conductivity is related to the behavior of conductors and insulators in the context of charging by induction.
  • The conductivity of a material determines its ability to allow the flow of electric charge. In the context of charging by induction, conductors with high conductivity, such as metals, allow the free movement of charges within the material. This enables the redistribution of charges on the surface of the conductor when an external electric field is applied, leading to the phenomenon of charging by induction. On the other hand, insulators with low conductivity resist the flow of charges, preventing the effective redistribution of charges and the occurrence of charging by induction.
• Describe how the model of conduction in metals, based on the free electron theory, explains the high conductivity of metals.
  • The model of conduction in metals, which is based on the free electron theory, explains the high conductivity of metals. In metals, the valence electrons are not tightly bound to individual atoms, but rather form a 'sea' of freely moving electrons. These free electrons are able to move throughout the metal lattice, carrying electric current with ease. The abundance of these free electrons, combined with their high mobility, results in the high conductivity observed in metals. This model helps understand the behavior of conductors in electrostatic equilibrium and the flow of electric current in metal-based electrical circuits.
• Analyze the relationship between conductivity, resistance, and Ohm's law, and explain how this relationship is crucial in understanding the Hall effect.
  • Conductivity, the inverse of electrical resistance, is a fundamental property that governs the flow of electric current in a material. Ohm's law, which states that the current through a conductor is directly proportional to the voltage applied and inversely proportional to the resistance, is a crucial principle in understanding the behavior of conductors. The Hall effect, which describes the generation of a transverse voltage in a conductor carrying a current and subjected to a magnetic field, is directly influenced by the conductivity of the material. The relationship between conductivity, resistance, and Ohm's law is essential in analyzing and interpreting the Hall effect, as the measured Hall voltage is directly related to the charge carrier concentration and mobility, which are determined by the material's conductivity.

Related terms

Electrical Resistance: The opposition to the flow of electric current within a material, which is the inverse of conductivity.

Charge Carriers: The particles, such as electrons or ions, that are responsible for the flow of electric current within a material.

Ohm's Law: The relationship between current, voltage, and resistance that governs the flow of electricity in a circuit.