B Triboelectric charging vs charging by conduction

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Rubbing two objects together generates a different result than mere contact due to the mechanical work involved in charge transfer. When objects are rubbed, they increase their contact area and create physical distortions, facilitating greater charge transfer. In contrast, simply bringing objects together involves minimal work and limited contact points at a microscopic level. This limited interaction results in only a small amount of charge transfer. Therefore, the process of rubbing enhances both the area of contact and the effectiveness of charge transfer.
versine
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Why does rubbing two objects together produce a different result than having them contact?
 
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versine said:
Why does rubbing two objects together produce a different result than having them contact?
I think there are to things at work here. Firstly, transferring charge requires Work to be done. In this case, it's actual mechanical work. Bringing two objects together involves less work than rubbing them together. Also, two objects, even described as flat are not actually flat; there will be very few touching points on a microscopic scale. Just bringing them together will, perhaps cause some small amount of charge transfer across those small areas. Rubbing will increase the total contact area over time and physical distortion (= work) of the surfaces will also cause charge transfer.
 
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