Experiment to Explain Frictional Electricity and Concept of Charging by Induction

Hope previous articles helped you in understanding Physics in better way. In this article I will discuss a simple experiment that will clear the concept of frictional electricity and concept of charging by induction.

So let’s begin with the experiment

For this simple experiment take a balloon and  a paper pin. Hang paper pin with a light thread. Now blow some air in the balloon and tie it. Rub the balloon with your hair and bring near the paper pin. See in the following fig. –

I strongly recommend to perform this experiment before proceeding ahead.

What did you see? You are quite familiar with the result of this experiment. Of course the balloon will start attracting the pin. Good… what is new then? Have you ever thought about the fact why balloon starts attracting pin ? Is it so simple as you are thinking it to be? The balloon is charged and charged bodies attract other charged bodies and that’s all, why the balloon is attracting the pin. Then I would like to remind you that you rubbed the balloon and not the pin so balloon was charged and not the pin. And now I would like to ask a question,  “whether the charge attracts charge or it can attract neutral bodies too?” Because the result of the above experiment can be explained only in following cases-

1. A charge can attract neutral bodies too.
2. Pin is also charged.

Can a charge interact with neutral bodies?

No, of course not. Charge only interacts with other charges. So the possibility about first point ends here.

Is pin charged?

Since we have two scenario and first one can’t be accepted, we have left only one choice. But again our mind brings up a question, “How?”. We didn’t rubbed the pin, then how it got the charge. And then I’ll say, “The way pin got the charge is what we call charging by induction”.