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Magnetic Flux

Magnetic flux (symbol the Greek letter (phi)) is a measure of quantity of magnetism. It is a scalar. It takes into account the strength and the extent of a magnetic field. It is a scalar quantity.

 
Symbol
Unit
Unit equivalent
Magnetic Flux
Wb (weber)
V s
Magnetic Field (or magnetic flux density)
B
T (tesla)
Wb m-2 or V s/m²

Magnetic flux is the product of the average magnetic field and the perpendicular area that it penetrates.

BA=

(B in the above equation is the component of B that is normal to A)

B (the magnetic field) is greater if there are more field lines in a given area - the density of the flux lines is great. You can think of the 'flux' as being a value that is proportional to the number of magnetic field lines that 'cut through' an area.

Two areas would have the same flux if one area was twice as big but had half the field strength of the first.