Задача 30261.

The square frame with sides a = 10 cm, through which flows the current I = 200 A, freely set in a uniform magnetic field with induction B = 0,2 T. Determine the job A, which is necessary to make when you turn the frame around an axis lying in the plane of the frame and perpendicular to the lines of magnetic induction by an angle 2n / 3.

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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