A magnetic field is a region where magnetic materials (like iron and steel) and also wires carrying currents experience a force acting on them.
A magnetic field can be identified by using iron fillings and they're invisible to the eye.
The magnetic field around a current carrying wire is created when the current flows through the wire. The field is made up of concentric circles with the wire in the centre.
The magnetic field round a coil of wire - the magnetic field inside a coul of wire (a solenoid) is strong and uniform. Outside the coil the magnetic field is just like the…