Understanding how materials interact with electric current is crucial in electronics. Materials are generally classified based on their ability to conduct electricity.
Conductors, like metals, have free electrons that allow electric current (the flow of charge) to pass through them easily. Examples include copper and aluminum.
Insulators, conversely, have electrons that are tightly bound to their atoms. This property prevents or significantly hinders the flow of electric current. They are used to prevent electrical shocks and short circuits.
Semiconductors fall in between conductors and insulators. Their conductivity can be controlled under specific conditions, making them vital for electronic devices like transistors and diodes.
Superconductors exhibit zero electrical resistance below a certain critical temperature, allowing current to flow without any energy loss. This is an extreme form of conductivity.
The question asks for a material that does not allow current to flow. Based on the definitions:
Therefore, the material that does not allow current to flow is an Insulator.
The conductivity of silicon is $\sigma$=10 ( $\Omega$ cm)$^{-1}$ Determine the drift current density J, if an electric field of E=15v/cm is applied.
Which of the following materials is not a semiconductor ?
(a) ZnO
(b) Carbon nanotube
(c) SiO2
(d) Copper
Which is correct ?
Semi conductors have