Задача 30249.

20 cm diameter Coil can be rotated about a vertical axis coinciding with one of the diameter of the coil. Revolution installed in the plane of the magnetic meridian, and it allowed for a current of 10 A. What torque must be applied to the coil, to keep him in the starting position? The horizontal component of the magnetic field of the Earth is equal to 15 A / m.

Detailed solution with a short recording conditions, laws and formulas used in the decision, the withdrawal of the calculation formula and the answer.
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