Задача 30489.

A coil with a diameter of 20 cm can rotate about a vertical axis coinciding with one of the diameters of the coil. The coil was installed in the plane of the magnetic meridian and a current I = 10 A was passed through it. Find the mechanical torque that must be applied to the coil in order to hold it in the initial position. The horizontal component of the earth´s magnetic field induction is taken to be 20 µT.

Detailed solution with a brief record of the conditions, formulas and laws used in the solution, derivation of the calculation formula and answer.
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