Torque on slowly moving electric or magnetic dipoles in vacuo

G. Asti; R. Coisson

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arXiv · 1810.08558

Torque on slowly moving electric or magnetic dipoles in vacuo

G. Asti·R. Coisson

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Abstract

The torque on a moving electric or magnetic dipole in slow motion is deduced using the Lorentz transformation of the fields to first order in v/c. It is shown that the obtained equations are independent of the model adopted for the dipole, whether it is of Amperian or Gilbertian type, thus showing the complete validity of the Amp\`ere equivalence principle even in dynamical conditions. The torque is made of three terms: beside that due to the direct torque on the dipole there are two more terms: one due to the torque on the associated perpendicular dual-dipole caused by motion, while the other is the inertial torque due to the displacement of the dipole which carries with it the field linear momentum, or the hidden momentum.

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G. Asti, R. Coisson. 2018-10-18. Torque on slowly moving electric or magnetic dipoles in vacuo. https://arxiv.org/abs/1810.08558

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