Solving a problem in physics section 62 point 14 electr

Solving a problem in physics section 62 point 14 electr

14. There is a coil length l = 20 cm and a diameter D = 2 cm. The coil winding is composed of N = 200 turns of copper wire, whose cross-sectional area s = 1 mm2. The coil is included in a circuit with some emf Using the EMF switch off, and the coil is short-circuited. After a time t after turning off the emf current in the circuit is reduced by 2 times?

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Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)