The direction of drift velocity for electrons in a metal is

CONCEPT:

• Drift velocity: The average velocity attained by charged particles, (eg. electrons) in a material due to an electric field.
  • Subatomic particles like electrons move in random directions all the time.
  • 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 mathematical expression of drift velocity is 

Where e = charge on electron, m = mass of electron, E = Electric field and τ = average relaxation time 

EXPLANATION:

• The mathematical expression of drift velocity is 

•  The mathematical expression of drift velocity is 

• Here negative sign shows that drift velocity is opposite to the direction of the applied electric field.