Question

Draw the pattern of magnetic
- field lines for a bar magnet​

Answer 1

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$\underline{\blacksquare\:\:\red{\footnotesize{\text{Charecteristics of Field lines :}}}}$

$\footnotesize{\text{(1) Magnetic lines of force started from North pole}}$

$\footnotesize{\text{and are ended on South pole . }}$

$\footnotesize{\text{(2) For the starting point different types of lines of }}$

$\footnotesize{\text{force can be found in the magnetic field rigion . }}$

$\footnotesize{\text{(3) The two lines of force never intersect each other . }}$

$\footnotesize{\text{hypothetical . There's no presence of such lines in }}$

$\footnotesize{\text{the magnetic field .}}$

$\footnotesize{\text{(4) In a point (any) in the M. F. rigion if we consider }}$

$\footnotesize{\text{a unit area vertically to the field lines then the }}$

$\footnotesize{\text{numbers of lines passing through that area is called }}$

$\footnotesize{\underline{\red{Number \:density}}.}$

$\footnotesize{\text{(5) In a point where this density is maximum the}}$

$\footnotesize{\text{magnetic field is much stronger there and the point }}$

$\footnotesize{\text{where this density is minimum then the magnetic }}$

$\footnotesize{\text{field is weak there .}}$

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