Page "Electric charge" Paragraph 18

In 1600, the English scientist William Gilbert returned to the subject in De Magnete, and coined the New Latin word electricus from ηλεκτρον ( elektron ), the Greek word for " amber ", which soon gave rise to the English words " electric " and " electricity.

" He was followed in 1660 by Otto von Guericke, who invented what was probably the first electrostatic generator.

Other European pioneers were Robert Boyle, who in 1675 stated that electric attraction and repulsion can act across a vacuum ; Stephen Gray, who in 1729 classified materials as conductors and insulators ; and C. F. du Fay, who proposed in 1733 that electricity comes in two varieties that cancel each other, and expressed this in terms of a two-fluid theory.

When glass was rubbed with silk, du Fay said that the glass was charged with vitreous electricity, and, when amber was rubbed with fur, the amber was said to be charged with resinous electricity.

In 1839, Michael Faraday showed that the apparent division between static electricity, current electricity, and bioelectricity was incorrect, and all were a consequence of the behavior of a single kind of electricity appearing in opposite polarities.

It is arbitrary which polarity is called positive and which is called negative.

Positive charge can be defined as the charge left on a glass rod after being rubbed with silk.