André-Marie Ampère founded and named the science of electrodynamics, which eventually came to be known as electromagnetism, according to Encyclopedia Britannica. The ampere, which is the unit for measuring electric current, is named after him.
Ampère showed that depending on whether the currents flow in the same or opposite directions, two parallel wires carrying electric currents repel or attract each other, respectively. From these experimental results he applied mathematics in generalizing physical laws. Ampère established the principle that eventually became called Ampère’s law. Ampère’s law states that the mutual action of two lengths of wires carrying current is proportional to their lengths and to the intensities of their currents.