From a ferromagnetic material, the magnetization curve of which is shown in Fig. 29.9 a, a core is made, the shape and dimensions of which in millimeters are shown in Fig. 30.14. On the core, turn to turn in one layer is wound on a winding of wire, the thickness of which (with insulation) is 0.6 mm. Determine the inductance of the coil when the current in the winding is 200 mA. Find the magnetic field energy and energy density.

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