d.c. Motor

• A d.c. motor converts electrical energy into mechanical energy.
• Understanding the operation of a d.c. motor requires familiarity with basic concepts, particularly electromagnetism and Fleming’s left-hand rule.
• A d.c. motor is composed of a rectangular coil that spins between the opposite poles of a magnet. This coil is sometimes referred to as an armature.
• The d.c. motor contains a split-ring commutator that reverses the current direction every half turn. This allows the motor to spin in one direction continuously.
• When current is supplied, the magnetic field generated by the coil experiences a force due to the permanent magnet’s magnetic field. This results in the coil turning.
• Follows Fleming’s left-hand rule. Where if you point your First finger in the direction of the Field (magnetic field from north to south), second finger in the direction of the Current, your thumb will point in the direction of the force/Motion.
• Motors also experience what is known as the motor effect. This is the force experienced by a current carrying wire in a magnetic field.
• The speed that the motor turns at is governed by the current’s magnitude and the strength of the magnetic field.
• Adjusting the power supply can control the speed and direction of rotation of the motor.
• Increasing the number of coils, current, or magnetic field strength will increase the motor’s speed. Conversely, reducing these factors will decrease the speed.
• The d.c. motor finds application in numerous devices that require a spinning or rotational motion like fans, electric vehicles and mixers.