Counter-Electromotive Force (CEMF)

Within a generator using a rotating armature, a conductor cut the magnetic lines of force inside the magnetic field.  A Voltage is induced in the armature conductors.  That induced voltage opposes the applied voltage; it counteracts a few of the applied voltage that decrease the current flow by the armature.  That induced voltage acts counter to applied voltage; therefore, it is known as counter-electromotive force (CEMF).