A long qn about charges...?

Question

If a charge glass rod is held near one end of an insulated uncharged metal rod, electrons are drawn to one end. Why does the flow of electrons cease? After all, there is an almost inexhaustible supply of them in the metal rod.

Answer 1

If electrons are flowing from one object to the next, then their respective charges change. As one looses electrons, it becomes more positive, and therefore starts attracting electrons. Meanwhile the object that was taking the electrons becomes more negative and starts to repel more electrons.

It is quite a balancing act ;)