Q3 of 47 Page 1

How is the drift velocity in a conductor affected with the rise in temperature ?


We know that


Where,


E=electric field


l=lenght of the conductor



And force on an electron is given by,


where ,e=charge on electron


V=electric potential


We know that


Equating the above two equations we get,




Using 1st equation of motion



where = drift velocity


Here,u=0



t=relaxation time




Since e , V , m , l are constant.



Increasing the temperature will increase the kinetic energy of electrons. As kinetic energy will increase the collisions will increase and hence relaxation time will decrease and since relaxation time is directly proportional to drift velocity hence drift velocity will also decrease.


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