Electromagnetism is the combined effect of electricity and magnetism.
Every electric current creates its own magnetic field.
Maxwell’s screw rule says that the magnetic field runs the same way a screw turns if you screw it in the direction of the electric current.
An electromagnet is a strong magnet that is only magnetic when an electric current passes through it. It is made by wrapping a coil of wire, called a solenoid, around a core of iron.
Electromagnets are used in everything from ticket machines and telephones to loudspeakers.
Magnetic levitation trains use very strong electromagnets to carry the train on a cushion of magnetic repulsion.
When an electric wire is moved across a magnetic field, an electric current is created, or induced, in the wire. This is the basis of every kind of electricity generation. Wind turbines generate electricity by using the wind to turn their blades. These drive magnets around inside coils of electric wire.
Fleming’s right-hand rule says that if you hold your right thumb, first and middle fingers at 90° to each other, your middle finger shows the direction of the induced current – if your thumb points in the direction the wire moves and your first finger points out the magnetic field.
Electromagnetism can be switched on and off, unlike permanent magnets.
Around every electric or magnetic object is an area, or electromagnetic field, where its force is effective.