Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

I have a pc with a metallic body on my CPU case. Yesterday suddenly the earthing wire of my CPU broke down and I was able to feel a little bit current on touching it's metallic body. But what I found to interesting was that when my finger rubbed on it's metal surface it was a feeling like when you rub the glass surface with a little bit wet surface a squkee sound come and your finger feel a little bit resistance on rubbing the surface and a very weird sound was coming out just like when you rub the to of a wine glass but the sound was little bit thick it was like ghnnnnnnnnnnnnnn and when I tried do that while wearing my sleepers i felt or heard nothing like that the surface felt completely smooth and there was no sound. Why was it happening?

share|improve this question
When you wear your slippers there is no path to the ground and no discharge.A discharge to the ground through your finger when not wearing them is what makes the sound. –  anna v Mar 6 '13 at 5:46
Yes i know that but why why it is little bit difficult rub the finger and why does it make sound. Why don't it go simply following me to the ground even when i rub my finger because the contact is continuous tne circuit don't breaks –  Akash Mar 6 '13 at 6:01
The current passing through the finger to the ground creates the attraction by denuding your finger from electrons which is then attracted to the positive metal surface (as the electrons leave). The sound is from small discharges where your finger is not flat on the metal and the current goes a bit through microns of air. I would advice to ground the frame as soon as possible. The sticking part shows that current is fairly strong. –  anna v Mar 6 '13 at 6:17
Yes I got it Thank's and I had wired the case yesterday only but Thank's for the advise –  Akash Mar 6 '13 at 6:20
Possible duplicate: physics.stackexchange.com/questions/2824/… –  Michiel Mar 6 '13 at 6:26

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.