Question

What is the effect of increase in temperature on drift velocity

Answer 1

As u know that in the formula for drift velocity there is a term called 'time constant' and it is directly proportional to drift velocity. It is actually the time between successive collisions that the free electrons undergo inside a conductor under an applied electricfield by the battery.So when temp. is increased the moving electrons gain kinetic energy, their velocity increase due to which they undergo collisions more frequently than before n hence the time constant decreases.As a result drift velocity decreases thereby decreasing the current. This is also the reason why we say resistance increase with increasing temp. n vice versa.