Benjamin Franklin's experiments in the mid-18th century established the concept of electric charge, introducing "positive" and "negative" terminology and the law of charge conservation. His investigations, notably the kite and thunderstorm experiment, demonstrated that lightning is electrical discharge, laying groundwork for electricity understanding and electrical technology development. The unit Coulomb Per Second (C/s), equating to the flow of 1 coulomb through a conductor in 1 second, represents electric current, with the SI unit known as ampere. This principle is fundamental in electric motors, where current flow generates a magnetic field, interacting within the motor to produce rotational force.