Magnetic Flux:
The group of magnetic field lines emitted outward from the north pole of a magnet is known as magnetic flux. A symbol for magnetic flux is Φ (phi).
The SI unit of magnetic flux is the weber (Wb). One weber is equal to 1 x 108 magnetic field lines.
Example: If a magnetic flux (Φ) has 5,000 lines, search the number of webers.
Φ = 5000 lines/ 1 x 108 lines/Wb = 5 x 103 / 108 - 50 x 10 -6 Wb= 50 µWb