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arXiv · 1405.6581

Demonstrations of magnetic phenomena: Measuring the air permeablity using tablets

Vitor O. M. Lara·Dayanne F. Amaral·Daiara Faria·Leonardo P. Vieira
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Abstract

We use a tablet to determine experimentally the dependencies of the magnetic field (B) on the electrical current and on the axial distance from a coil (z). Our data shows a good precision on the inverse cubic dependence of the magnetic field on the axial distance, $B \propto z^{-3}$. We obtain with good accuracy the value of air permeability $μ_{air}$. We also observe the same dependence of $B$ on $z$ when considering a magnet instead of a coil. Although our estimates are obtained through simple data fits, we also perform a more sophisticated error analysis, confirming the result for $μ_{air}$.

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Vitor O. M. Lara, Dayanne F. Amaral, Daiara Faria, Leonardo P. Vieira. 2014-05-26. Demonstrations of magnetic phenomena: Measuring the air permeablity using tablets. https://doi.org/10.1088/0031-9120%2F49%2F6%2F658

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