Electromotive Force ME350 A voltage is induced in a wire moved in a magnetic field >Generators(发电机) emd=(y×B)·l Induced Velocity of wire(m/s) voltage (volt) eind is also called electromotive force(EMF感应电动势) eind =vBl (7=the wire length) Vhat happens if a“free” current-carrying wire is placed in a magnetic field?13 ME 350 • A voltage is induced in a wire moved in a magnetic field ¾Generators（发电机） B + + + v eind • l (l = the wire length) = ×Bv )( Induced voltage (volt) Velocity of wire (m/s) l --- eind =vBl eind is also called electromotive force (EMF感应电动势) eind What happens if a “free” current–carrying wire is placed in a magnetic field? Electromotive Force