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प्रश्न
Transformers are used ______.
विकल्प
in DC circuits only
in AC circuits only
in both DC and AC circuits
neither in DC nor in AC circuits
उत्तर
Transformers are used in AC circuits only.
Explanation:
When a DC supply is provided to a transformer, there will be no change in flux with time across the coils of the transformer. So, there will be no induced emf in the secondary coil due to changing current in the primary coil. Hence, the transformer cannot operate in DC because of the violation of its working principle.
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