Question

Recall that the density J of current flowing through a material can be written in terms of microscopic properties of the material: ,where n is the density of current carriers,q isthe charge of one current carrier, and $v_d$ is the driftvelocity of a current carrier. In a metal, the current carriers are electrons.

The drift velocity is the component of the current-carrier's velocity due to acceleration from the electric field in the conductor. This corresponds to the averagespeed of all of the current carriers in the conductor. The current carriers also have random thermal motions, but the randomness causes the velocities due tothermal motion to cancel when averaged over a large number of current carriers. If the electric field inside of the conductor has magnitude E, and the charge q isaccelerated from rest for a time , what is the final speed vof the charge?

Express the speed in terms of E, q, , and hte mass m of thecharge

v= ?

Answer 1

V = (Eq/m)t