SEPTA Electrician Practice Test

The armature’s job is to carry current through its windings and, in the presence of a magnetic field, experience forces on those conductors that produce torque, turning the rotor. When electricity flows through the armature windings inside the machine’s magnetic field, those forces act on the conductors and generate the rotational force that drives the motor. It’s not primarily a storage of energy—the magnetic energy is mostly in the field or inductance, not in the armature itself. The armature isn’t the outer housing; that enclosure is separate. And the brush gear isn’t independent of current—it transfers current to the armature via the commutator. That interaction between current and magnetic field creating torque is what the armature does best.