Charging by Friction

Atoms are the building blocks of matter. Note that objects are composed of different types of atoms and groupings of atoms. The existence of diverse atoms in objects provides different objects with diverse electrical properties. An example of this type of property is known as electron affinity. This refers to the comparative amount of attraction that a material has for electrons. If atoms of a material have a high electron affinity, then that material will have a comparatively high attraction for electrons. This property of electron affinity will be important in charging by friction or rubbing.

The frictional charging procedure happens because there is a shift of electrons between two objects that are rubbed together. One object A has a much greater attraction for electrons than the other object B. As a result, the atoms of the object A (with the greater attraction) pull electrons from the atoms of the object B (with lesser attraction), leaving both objects with an unevenness of charge. Object A has a surplus of electrons and object B has a lack of electrons. Having a surplus of electrons, object A is charged negatively. On the other hand, the lack of electrons on object B gives it a positive charge. The two objects A and B have become charged with differing types of charges as a result of the shift of electrons from the least electron attractive matter to the more electron attractive matter.