How can electric charges be produced by rubbing?

Electron migration from one negatively charged material to another occurs when two materials are rubbed against one another, leaving an excess or deficiency of electrons (negatively charged particles) relative to protons (positively charged particles).

A specific number of electrons are captured by one material from another as a result of rubbing; as a result of this migration of electrons, one material becomes negatively charged (due to an excess of electrons over protons), while another material simultaneously becomes positively charged (due to a deficiency of electrons in comparison to protons).

Electron migration occurs only when one material is a stronger holder of its electrons than the other and is largely dependent on the properties of the materials rubbed against each other.

It should be noted that light negatively charged electrons are always moving within the material, forming a "electron cloud," in contrast to heavy protons, which are carriers of positive electric charge. As a result, during rubbing, they can migrate from one material to another if the forces holding the electrons inside are noticeably stronger than the corresponding forces in the other.

Electric charges can be produced by rubbing two objects together, which causes friction between their surfaces. This friction results in the transfer of electrons from one object to the other, leading to a buildup of electric charge on the surfaces of the objects involved in the rubbing process.