The motor is an electrical device which can convert electrical energy into mechanical energy, using the principles of electricity and magnetism.
- Stator – the permanent magnets.
- Rotor – the rotating part which contains conducting coils inside it,
- Shaft – outputs the mechanical energy
- Commutator – to apply alternating current to the rotor.
- Brushes – To make contact between power supply and commutator.
Working Principle
When the power switched on, the brushes supply current to the commutators. These commutators are attached to the rotating coils, one to each end. Current passes from commutators into the coil, placed in between the poles of permanent magnets, stator. When current moves in the coil, the magnetic field is induced around the coil.
This magnetic field comes in contact with the magnetic field of the permanent magnets and due to the characteristic of the magnetism that like poles repel each other and unlike poles attracts, the coil starts to rotate. When the rotor rotates the shaft attached to it also rotates, thereby converting the applied electrical energy into mechanical energy.
Electric Generator
The device that can convert the mechanical energy to electrical energy is called a generator. The hardware requirements of the generator are the same but working principle differs. Here when the mechanical energy is applied to the shaft, the rotor rotates and this movement of the rotor between the permanent magnets starts generating electricity inside the coils of the rotor. This electricity is collected by the brushes.
| Sl. No. | Differentiating Property | Motor | Generator |
| 1 | Definition | An electric motor is a machine that converts electrical energy to mechanical energy. | An electric generator is a machine that converts mechanical energy to electrical energy.` |
| 2 | Rule | Electric motor follows Fleming’s left-hand rule. | Electric generator follows Fleming’s right-hand rule. |
| 3 | Principle | The working principle of a motor is based on the current-carrying conductor that experiences a force when it is kept in the magnetic field. | The working principle of generator is based on electromagnetic induction. |
| 4 | Driving force for shaft | The shaft of an electric motor is driven by a magnetic force which is developed between the armature and field. | The shaft of an electric generator is connected to the rotor which is driven by a mechanical force. |
| 5 | Current Usage | In a motor, current is supplied to the armature winding. | In a generator, current is produced in the armature winding. |
| 6 | Example | Ceiling fans, cars, etc. are all examples of motor. | In power stations, generator is used to generate electricity. |
