text: what is the differnce between current and charge? also wat r transformers? electric current is the rate of charge flow past a given point in an electric circuit, measured in coulombs/second which is named amperes.  a transformer is an electrical device that transfers energy from one circuit to another by magnetic coupling with no moving parts. a transformer comprises two or more coupled windings, or a single tapped winding and, in most cases, a magnetic core to concentrate magnetic flux.  transformers are used to convert between high and low voltages, to change impedance, and to provide electrical isolation between circuits.