The name for interactions between electrical and magnetic phenomena. The science of electromagnetics deals with the application of electrical principles and apparatus to magnetic phenomena. Transformers, antennæ, and phonograph cartridges are electromagneticelectro-magnetic devices. Longer explanation: There are four known forces operating in the universe: strong and weak nuclear forces, gravity, and electromagnetism, the latter two being the two manifestations of electromagneticelectro-magnetic force. These are mutually affective, i.e., a magnetic field can influence an electric field and vice versa as an electromagneticelectro-magnetic wave consists of both an electric field and a related perpendicular magnetic field. The electromagneticelectro-magnetic spectrum consists of (in order of increasing frequency) radio waves, microwaves, infrared light (heat), visible light, UV light, X-rays and gamma rays. All electromagneticelectro-magnetic waves propagate at the same speed, the speed of light.