What does a rheostat control?

What does Rheostat controls? electron drift velocity or quantity of electrons? We know I=nAve I=current n=quantity of electron A=conductor area e=electron charge v=drift velocity (Asked  Partha)

Where is electricity stored after it is generated but before it is supplied?

This question was posted by Chithraja. This is a common doubt arising naturally in the minds of children as well as adults who think. But they never ask, or if they ask the questions remain unanswered. I will explain the question itself first. When we switch on a bulb we get the energy. But what happens to the electricity [...]