🔍 Key Concepts

• Basic parts of a DC motor: armature, field coils, commutator, brushes • Function of the commutation system: how current is switched in the rotating armature to keep torque in one direction • Difference between stationary parts (fixed on the frame) and sliding contacts (parts that touch the rotating commutator)

💭 Think About

• Which component actually makes and breaks electrical contact with the rotating commutator segments as the motor turns? • Which of these choices is responsible for switching the direction of current in the armature coils so the motor doesn’t reverse direction every half turn? • Look at each option and ask: does this part move with the rotor (armature), stay fixed to the frame, or is it a sliding contact between the two?

✅ Before You Answer

• Be clear on the role of field coils: they create the magnetic field but do they switch current in the armature? • Identify which part provides electrical contact to the moving armature while staying fixed to the outside housing. • Verify which component is directly involved in commutation (changing which armature coils are energized as it rotates).