Final answer:
Physicist James Clerk Maxwell developed a theory known as Maxwell's equations to explain the relationship between electricity and magnetism. His equations elegantly express the concepts of electromagnetism and predict the existence of electromagnetic waves, including visible light.
Step-by-step explanation:
Physicist James Clerk Maxwell developed a theory that explained the relationship between electricity and magnetism, known as Maxwell's equations. He brought together the work of previous physicists such as Oersted, Coulomb, Gauss, and Faraday and added his own insights to create a comprehensive theory of electromagnetism. Maxwell's equations elegantly expressed the concepts of electromagnetism and predicted the existence of electromagnetic waves, including visible light.