By fine wire bent into a rectangle

By fine wire bent into a rectangular current flows I = 60 A. The length of the sides of the rectangle are a = 30 cm and b = 40 cm. Determine the magnetic induction B at the point of intersection of the diagonals.

Task 30991. Detailed solution shorthand terms, formulas, laws used in the decision, the withdrawal of the calculation formula and the response.

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