Are the field lines the same as the magnetic flux density $\vec{B}$, or magnetic field intensity $\vec{H}$?

Or is it neither of them and defined just to easily explain the magnetic field by using iron filings or something?


1 Answer 1


Magnetic field lines are a way to represent information about a magnetic field at a point. They are a way for us to visualise the direction of the field (shown by arrows on the field lines) and the relative strength of the field (shown by the density of the field lines, where more dense field lines means a stronger field).

  • $\begingroup$ "Note that the field lines don’t give us any quantitative information." This is not strictly true. Maxwell (Unit) $\endgroup$
    – Farcher
    Oct 6, 2021 at 7:50
  • $\begingroup$ @Farcher Apologies, I’ll change my answer $\endgroup$
    – UnrulyTank
    Oct 6, 2021 at 8:14
  • $\begingroup$ If we can get the exact value expressed in the unit of Maxwell from the magnetic field line, then we can surely convert the unit of the value from Maxwell into Weber, which is the unit of magnetic flux(Maxwell is the unit of magnetic flux as well, but I'm more familiar with Weber). Does it mean that magnetic field line is exactly the magnetic flux? (Assume that we scatter enough iron filings to have no problem fully representing the magnetic field) $\endgroup$
    – achilles
    Oct 6, 2021 at 11:55
  • $\begingroup$ I got that magnetic field lines can't be magnetic flux because magnetic flux is defined as a vector field, but magnetic field lines are not. $\endgroup$
    – achilles
    Oct 7, 2021 at 2:58

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.