When 2 inductors share the same magnetic field they become coupled and besides their self inductance they have a mutual inductance as well. For this circuit:

Now current entering one coil marked with a dot, produces a current exiting the couple coil at its dotting end. In L1 current enters from the dotted end so this creates a current which exits from the dotted end of L2 and in L2 current enters from the dotted end so this again creates a current which exits from the dotted end of L1 so we get 2 voltage drops from self inductance of each coil and 2 voltage drops from the mutual inductance of the coupled coils.

so that is translated to this equation:

Now obviously :

The total inductance of the circuit becomes

the value of the mutual inductance is: (with k=1)

$L_{T}=4 \text{H}$

and the equation of current of this circuit becomes

posted about 3 years ago

CC BY-SA 4.0

3y ago by Elliot Alderson‭

MissMulan‭

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