free electrons drift theory
Answers
When electrons are subjected to an electric field they do move randomly, but they slowly drift in one direction, in the direction of the electric field applied. The net velocity at which these electrons drift is known as drift velocity
This theory has some assumptions; they are: The valence electrons of metallic atoms are free to move in the spaces between ions from one place to another place within the metallic specimen similar to gaseous molecules so that these electrons are called free electron gas.
Explanation:
The free electrons move in a conductor with random velocities and random directions. When we apply an electric field across the conductor, the randomly moving electrons experience an electrical force in the direction of the field.
Due to this field, the electrons do not give up their randomness of motion, but they will shift towards higher potential with their random motion. That means the electrons will drift towards higher potential along with their random motions. Thus, every electron will have a net velocity towards the higher potential end of the conductor, and we refer this net velocity as the drift velocity of electrons. Hopping, you understand the definition of drift velocity. The current due to this drift movement of electrons inside an electrically stressed conductor, is known as drift current. It is needless to say that every electric current is “drift current.