Electromagnets
Making a Simple Electromagnet
To make a simple electromagnet, wind a copper wire around a big iron nail and connect the ends of the wire to a dry cell. Once electricity flows through the coil, the nail will act just like a real magnet with north and south poles. It loses its magnetism when the electric current is cut off. As the electric current flows through the wire, a magnetic field is formed around the wire. Since an electromagnet has wires coiled around it, as soon as electricity flows through it, the coils generate the magnetic field.
Strengthening of Electromagnets
Since an electromagnet relies on electricity to generate a magnetic field, its ability to attract metal objects can be controlled. You can make an electromagnet stronger or weaker by adjusting the length of the pathway of electricity through the coils of wire.
Increasing the number of coils of wire provides the electromagnet a longer surface for its magnetic field to occupy. In short, more loops mean more space for the magnetic field to act on the electromagnet.
Increasing the amount of electricity flowing through the coils also makes the magnetic field stronger. The secret of an electromagnet's magnetic field is electricity. The more electricity provided, the more current flows through the coil. The greater the current in the coil is, the stronger is the magnetic field.
