Brief History of Electric Force

1. Brief History of Electric Force 600 BCThales of Miletos. “Thales was the first known Greek philosopher, scientist and mathematician. He is credited with five theorems of elementary geometry.” He could move feathers with a piece of amber, so long as he first rubbed it with cat fur. Greek word for amber is elektron 1600s Niccolo Cabeo found and proved that electric forces could also be attractive, as well as repulsive, and that a charged body could attract a non-electrified one. 1729Stephen Gray found that this “electric force” could be sent over copper wires, which in turn proved that electricity wasn’t an exclusive property of a material. 1733 Charles Francois du Fay discovered negative and positive charges, called them resinous(-) and vitreous(+) 1780s Coulomb and his torsion balance, proving the electric force is inverse square over a distance, and finding k coulomb’s constant. 1745 E.G. von Kleist & Prof. von Musschenbroek, Leyden, discovered independently that a glass vessel filled with water and charged from a frictional source could store the charge. "Leyden Jar", the first electrical condenser. 1799 Alessandro Volta (1745-1827) is due to his invention, in late 1799, of the "Pile", the first battery in history. Thales of Miletos Figure shows that the electric force of a rubbed glass could be sent, through a wire, to the body of a person. Leyden Jar: If metal coatings inside & outside a glass jar are charged oppositely, they give a spark when connected Original drawings of Coulomb’s torsion balance for measuring properties of the Electric force. Original drawings of his Piles by Volta: the "chain of cups" apparatus (upper), & the "columnar apparatus" (middle & lower). Zn and Ag (silver)