the branch of physics concerned with electromagnetic phenomena
magnetism produced by an electric current; "electromagnetism was discovered when it was observed that a copper wire carrying an electric current can magnetize pieces of iron or steel near it"
the lagging of an effect behind its cause; especially the phenomenon in which the magnetic induction of a ferromagnetic material lags behind the changing magnetic field
memory device consisting of a long thin plastic strip coated with iron oxide; used to record audio or video signals or to store computer information; "he took along a dozen tapes to record the interview"
having an indicated pole (as the distinction between positive and negative electric charges); "he got the polarity of the battery reversed"; "charges of opposite sign"
of or belonging to or characteristic of this earth as distinguished from heaven; "earthly beings"; "believed that our earthly life is all that matters"; "earthly love"; "our earthly home"
any of the various theories or doctrines or philosophical systems that attempt to explain the phenomena of the universe in terms of some immanent force or energy
marked by qualities giving the power to produce an intended effect; "written propaganda is less efficacious than the habits and prejudices...of the readers"-Aldous Huxley; "the medicine is efficacious in stopping a cough"