[Physics] get a static shock from the metal taps when wearing a fluffy dressing gown


I recently bought a new dressing gown and I am experiencing a lot of static electricity build up when wearing it.

It got me thinking, where are those electrons coming from? I would have thought that if the robe is rubbing electrons off my body, then as a unit of (me + robe), we still have the same number of electrons (they just moved from me to the robe). So then why do I receive a shock every time I touch the metal taps in the bathroom?

Also any tips on preventing it appreciated! A friend mentioned something about surfactants in washing powder and suggested I wash it. Why would that help?

Note: There is a related question How To Avoid Getting Shocked By Static Electricity, but it only answers the 2nd part of the question, I've highlighted in bold the bit I'd like a physics explanation for.

Best Answer

They have moved from you to the robe, but it's your body, with its normal electrostatic balance now gone, that is making the complete connection between the tap and say, a wet floor.