A large number of free electrons are present in metals.Why is there no current in the absence of electric field across it ?

A large number of free electrons are present in metals. Why is there ni current in the absence of elctric field across it?

The number density of free electrons in a metal piece is a very large of the order of 10^(+29) m^-3 . Why is there no current in the metal piece in the absence of electric field across it ?

The number of electrons present in 3d of Cu+ is ........

Drift velocity in a metallic conductor: At room temperature there are large number of free electrons having zero average velocity, but when electric field is applied, the free electrons start moving in a direction opposite to the direction of the applied field with a velocity called drift velocity. The magnitude of electric field set up across the ends of the conductor is given by

Drift velocity in a metallic conductor: At room temperature there are large number of free electrons having zero average velocity, but when electric field is applied, the free electrons start moving in a direction opposite to the direction of the applied field with a velocity called drift velocity. Magnitude of acceleration produced in each electron by the electric field is

Drift velocity in a metallic conductor: At room temperature there are large number of free electrons having zero average velocity, but when electric field is applied, the free electrons start moving in a direction opposite to the direction of the applied field with a velocity called drift velocity. Mobility of free electron is

Drift velocity in a metallic conductor: At room temperature there are large number of free electrons having zero average velocity, but when electric field is applied, the free electrons start moving in a direction opposite to the direction of the applied field with a velocity called drift velocity. Average thermal velocity of the electron is

Drift velocity in a metallic conductor: At room temperature there are large number of free electrons having zero average velocity, but when electric field is applied, the free electrons start moving in a direction opposite to the direction of the applied field with a velocity called drift velocity. The magnitude of drift velocity is