Magnetic Flux

Magnetic flux, $\varphi$, is defined as the number of lines of magnetic force passing through a specific area in space, $A$. The unit for magnetic flux is Weber ($\text{Wb}$).

Magnetic Flux Density

Magnetic flux density is defined as the number of lines of magnetic force passing through unit area.

$$B=\frac{\varphi }{A}$$

The symbol used for magnetic flux density is $B$ and its unit is $\text{Wb}/{\text{m}}^2$ or Tesla ($\text{T}$).