Question

How does the random motion of free electrons in a conductor get affected when a potential difference is applied across it's ends?

Answer 1

random thermic motion occurs when no p.d is applied.....

so when p. d is applied across it's ends d free electrons start traveling from d positive terminal to d negative terminal of d source of p. d (as per conventional current)....

d electrons will face collisions with other electrons as well as with the relatively heavy positive ions called lattice

Answer 2

Explanation:

When potential difference is applied across the ends of a conductor, the electrons are pushed towards the positive end. Hence, drift velocity gets superposed on their thermal velocity or random motion, and they get drifted towards the positive end of the conductor and hence constitute electric current.