Answer :
The index of refraction of the substance M = 0.45 mH. The refractive index n is the ratio of the speed of light c in a vacuum to the speed of light c' in a medium.
For the system described in the statement, the induced emf in both coils is given by. In other words, the induced emf in one coil is produced by the change in current in the other coil. It can be assumed that a current of 8.0 A belongs to the second coil and an induced emf of 3.00 V develops in the first coil. The current in the second coil turns off at 1.20 ms. Using the previous information, we know: Coil is 0.45mH.
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