1. The problem statement, all variables and given/known data Why must the coil in an electric motor kit be wound in only one direction? Why must the current change direction every 180 degrees in the motor? 2. Relevant equations No relevant equations. Just a simple answer. 3. The attempt at a solution NI-Prentice Hall DC Motor Theory states that The armature (rotor) of a DC motor has coils of wire wrapped around its core. The ends of each coil are terminated at commutator segments located on the left end of the shaft. The brushes make contact on the commutator to provide current for the armature.