Two short bar magnets of magnetic moments $m$ each are arranged at the opposite corners of a square of side $d$ such that their centres coincide with the corners and their axes are parallel. If the like poles are in the same direction, the magnetic induction at any of the other corners of the square is

  • A

    $\frac{{{\mu _0}}}{{4\pi }}\frac{m}{{{d^3}}}$

  • B

    $\frac{{{\mu _0}}}{{4\pi }}\frac{{2m}}{{{d^3}}}$

  • C

    $\frac{{{\mu _0}}}{{4\pi }}\frac{m}{{2{d^3}}}$

  • D

    $\frac{{{\mu _0}}}{{4\pi }}\frac{{{m^3}}}{{2{d^3}}}$

Similar Questions

Assume the dipole model for earth’s magnetic field $\mathrm{B}$ which is given by

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$ = \frac{{{\mu _0}}}{{4\pi }}\frac{{2m\,\cos \theta }}{{{r^3}}}$

${{\rm{B}}_H} = $ Horizontal component of magnetic field

${{\rm{B}}_H} = \frac{{{\mu _0}}}{{4\pi }}\frac{{m\,\sin \theta }}{{{r^3}}}$

$\theta $ $= 90^{°}$ -latitude as measured from magnetic equator.

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