The working principle of DC generator is that the alternating electromotive force induced in the armature coil is transformed into DC electromotive force by the commutator cooperating with the commutation effect of the brush.

The direction of the induced electromotive force is determined according to the right hand rule (the magnetic induction line points to the palm of the hand, the thumb points to the direction of the conductor movement, and the other four fingers point to the direction of the induced electromotive force in the conductor).

working principle:

The direction of the force on the conductor is determined by the left-hand rule. This pair of electromagnetic forces forms a torque acting on the armature, which is called electromagnetic torque in rotating motor. The direction of torque is counterclockwise, trying to make the armature rotate counterclockwise. If the electromagnetic torque can overcome the resistance torque on the armature (such as the resistance torque caused by friction and other load torque), the armature can rotate counterclockwise.

DC motor is a kind of motor which depends on DC working voltage. It is widely used in tape recorders, video recorders, video disc players, electric shavers, hair dryers, electronic watches, toys, etc.