how does drift velocity of electron in a metallic conductor vary with temperature?
vd = (TeE)/m
vd = is drift velocity
e = charge of electron
E = electric field
m = mass of electron
T = relaxation time
which implies that drift velocity is directly proportional to relaxation time.
relaxation time is the time interval between successive collisions of an electron during its flow in a conductor. On increasing temperature, the electrons move faster and more collisions occur quickly.
Hence relaxation time decreases with increase in temperature
which implies that drift velocity also decreases with temperature.