How to make an electric motor
How to make the simplest electric motor
Warning! Only under adult supervision.
- battery pack with batteries and crocodile clips;
- copper wire;
- wooden stick;
- neodymium magnet.
Wind a copper wire tightly around a battery several times. Wrap the free ends of the wire around the resulting coil several times to fix the wires together. Using sandpaper, strip the insulation from only one side of each free end of the wire. Break off two small pieces from a wooden stick and insert them between the batteries. Fix the crocodile clips on the pieces of wood. Set a neodymium magnet on top of the batteries. Place the ends of the loop on the crocodile clips and tap the coil gently – it will start to rotate, thereby starting the engine!
When the stripped section of the wire comes into contact with the crocodile clips, this creates a closed circuit, through which current begins to flow. The loop rotates, trying to assume a certain position due to its interaction with the field of the permanent magnet. Stripping the ends of the wire only on one side prevents the loop from taking the desired position: when the insulated section comes into contact with the “crocodiles,” the circuit opens, and the magnetic field ceases to act on the wire. The loop continues to rotate due to inertia, overshooting its “comfortable” position, and its stripped sections once again touch the crocodile clips, closing the circuit again. Thus, revolution after revolution, the engine continues to spin.
You can get this and other experiments in the MEL Physics subscription!