Magnetism is a force of attraction or repulsion that acts at a distance. it is due to a magnetic field, which is caused by moving electrically charged particles. it is also inherent in magnetic objects such as a magnet. A magnet...
Category - Physics
The foundation of all experimental science and technology is measurement. The result obtained from any measurement will contain some uncertainty. Such an uncertainty is termed error. Any calculation made using the measured values...
1. What is a semiconductor? The materials in which the electrical conductivity lies between conductors and insulators are called semiconductors. They have resistivity value between 10-4 to . The electrical conductivity of...
The concept of length in physics is related to the concept of distance in everyday life. Length is defined as the distance between any two points in space. The SI unit of length is metre. The objects of our interest vary widely...
In intrinsic semiconductor, the electron density is equal to hole density. In extrinsic semiconductor the electron and hole densities are related by ni2 = N⋅P ...
Expression for electrical conductivity in intrinsic semiconductor The general expression for the electrical conductivity, σ = neμ The intrinsic electrical conductivity, σi = [neμe + peμh] But n = p = ni Therefore ...
The semiconductors are further classified into intrinsic semiconductors and extrinsic semiconductors. Intrinsic semiconductors A semiconductor in which holes and electrons are created only by thermal excitation across the energy...
The electrical conduction in a semiconductor is due to free electrons in the conduction band and holes [vacant sites] in the valence band. The free electron current is in the opposite direction to the conventional current. But...
When an electric field [E] is applied to a semiconductor, the free electrons and holes are drifted in opposite direction of the electric field., due to this a current is produced called drift current Vd. Vd ∞ E Vd = μ...
1. What is a conducting material? Metals are good conductors due to the absence of energy gap and the presence of free electrons with low resistivity. 2. Define drift velocity of electrons. Drift velocity (Vd) is the velocity...
