The electric current in a long wire creates a magnetic field around the wire.ย Magnetic field lines (๐ต) form circles around the wire. The direction of thoseย lines depends on the direction of the current (I) and can be determined using the right-hand rule. The magnitude of the magnetic induction: ๐ต = (๐0I/2๐r), where ๐0 =4๐ โ 10^(โ7) โ(๐โ๐)/A โ the permeability of free space, I โ the magnitude of theย current vector, r โ distance from the wire. The magnitude of the magnetic induction: ๐ต = (๐0I/2๐r) , where ๐0 = 4๐ โ 10^(โ7) โ(๐โ๐)/Aโ the permeability of freeย space, I โ magnitude of the current vector, rโ distance from the wire.
This poster summarizes how the magnetic field changes based on the number of wires, their location, current direction, and its strength in those wires. As you may observe, even the same wires may create an absolutely different magnetic field based on the factors mentioned above.
