> but the resulting charge depends on where in the series that thing was relative to glass You'd think we would understand the science of contact/static/tribo

> but the resulting charge depends on where in the series that thing was relative to glass You'd think we would understand the science of contact/static/tribo electricity by now... And yet this posted 1 day ago: "Static electricity depends on materials' contact history" https://phys.org/news/2025-02-static-electricity-materials-contact-history.html https://phys.org/news/2025-02-static-electricity-materials-c... Historically, several studies have suggested that insulators could be ordered based on the sign of charge they exchange, from the most positive to the most negative. For instance, if glass charges positively to ceramic and ceramic does the same to wood, then glass (usually) charges positively to wood. Thus, glass, ceramic, and wood would form a so-called "triboelectric series." The problem with these triboelectric series, according to Waitukaitis, is that different researchers get different orderings, and sometimes even the same researcher does not get the same order twice when they redo their own experiment. Discuss: https://news.ycombinator.com/item?id=43134657 https://news.ycombinator.com/item?id=43134657 And https://en.wikipedia.org/wiki/Triboelectric_effect#Explanations_and_mechanisms https://en.wikipedia.org/wiki/Triboelectric_effect#Explanati... There are many cases where there are triangles: material A is positive when rubbed against B, B is positive when rubbed against C, and C is positive when rubbed against A, an issue mentioned by Shaw in 1914.[29] This cannot be explained by a linear series; cyclic series are inconsistent with the empirical triboelectric series.[75] Furthermore, there are many cases where charging occurs with contacts between two pieces of the same material.[76][77][47]