Have you ever thought of the speed in which your rooms get lighted up ,when you just turn your switch on. Some of you may have .Of course , I had that curiosity and I am happy to share the results with you.
It was interesting to notice that the speed of an electron whose motion results in electric current is smaller than that of a nail! You can flip a light switch and watch a lamp five feet away turn on in an instant .But to watch a single electron travel from the switch to the light , you would have to wait for an hour.
The speed at which electrons flow through a wire is called “electron drift”,and it happens at around 0.1 – 0.4 millimeters per second.Pit an electron against your average snail,which travels around 3- 10 millimeters per second,and it’s not even a contest .But if electrons move so slowly, how can a switch turn a lamp instantaneously? Think of a tube filled with balls:if you add a a ball at one end ,a ball will come out at the other end at almost the same instant,even though each ball didn’t move that far on its own.
Like wise ,if we replace our tube with a copper wire and the balls with electrons,the same results can be obtained .Those electrons are packed in so tightly that even a small movement will travel down the wire from electron to electron at an impressive speed , letting you turn on the lights without having to wait for electrons to travel the whole way.
First Year Student