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Electricity and Magnetism
Magnetic
Flux
If B is at 90° to the area, A, then the total magnetic flux, "passing through" A is defined to be
The units of flux are Tm˛ and 1 Tm˛ = 1 Weber If B is not at 90° to the area:
the component of B which acts at 90° to A is Bcos a. So, in this case, the flux "passing through" the area is defined to be
If a flux, f, "passes through" a coil of N turns then the coil is said to be linked to the flux (or threaded by the flux) and we define the quantity "flux linkage" as

