Why like-charged particles of dielectric materials can be attracted to one another

Calculations of surface charge density provide evidence of the physical effects responsible for particles of a dielectric material carrying the same sign of charge being attracted to one another. The results show that attraction requires a mutual polarisation of charge leading to regions of negative and positive surface density close to the point where the particles make contact. These results emphasise the significance of using charged particle models where the surface charge is non-stationary.

Force calculated to exist between two positively charged particles; when this becomes negative the particles are attracted to one another.Figure optionsDownload high-quality image (36 K)Download as PowerPoint slideResearch highlights
► Like-charged particles of dielectric materials can be attracted to one another.
► Calculations represent charged particles as having a constant, but free and dynamic surface charge.
► Mutual polarisation of the surface charge leads to attraction.