Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
Materials which easily allow the passage of electric current are known as _________
Insulators
Conductors
Dielectrics
Semi-conductors
Conductors
Conductors are materials that possess a high density of free charge carriers, typically electrons, which can move freely through the lattice structure. This mobility allows for the rapid passage of electric current when an external potential difference is applied.
Conductors are materials that possess a high density of free charge carriers, typically electrons, which can move freely through the lattice structure. This mobility allows for the rapid passage of electric current when an external potential difference is applied.
J=╧ГE тАФ Current density definition
I=nAqvdтАЛ тАФ Current in terms of drift velocity
In conductors, the valence band and conduction band overlap, or the bandgap is extremely small, allowing electrons to move into the conduction band with minimal energy. According to Ohm's Law, when a potential difference V is applied, the drift velocity of these free electrons creates a current I proportional to the conductivity ╧Г of the material.
High electrical conductivity and low resistivity.
Abundance of free electrons in the conduction band.
Positive temperature coefficient of resistance (for metals).
Examples include Copper, Aluminum, Silver, and Gold.
Minimal energy loss during transmission.
Efficient transfer of electrical signals.
Prone to short circuits if not insulated.
Subject to ohmic heating (I2R losses).
Power transmission lines.
Electrical circuit wiring.
Electronic components and PCB traces.
| Feature | Conductors | Insulators |
|---|---|---|
Conductivity | Very High | Very Low |
Energy Bandgap | Overlapping/None | Large (>5 eV) |
The SI unit of conductivity is Siemens per meter (S/m).
Insulators have extremely high resistivity and prevent current flow.
Dielectrics are insulators that can be polarized by an electric field.
Semiconductors have properties between conductors and insulators, controllable by doping.
B is correct тАФ Conductors are materials with high free electron density, facilitating the easy passage of electric current.
Always remember: conductors have a positive temperature coefficient, meaning their resistance increases as temperature rises, unlike semiconductors or insulators.