Q8 of 51 Page 329

Transformers are used

Transformers only work in AC circuits where they step up or step down the voltage.


In a DC circuit, there is no change in flux with time across the coils of the conductor, since the current is constant. So, there will be no induced emf in the secondary coil due to the change in flux from changing current in primary coil. For this reason, DC circuits do not obey the principle of transformers.

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