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प्रश्न
State the principle of working of a transformer. Can a transformer be used to step up or step down a d.c. voltage? Justify your answer.
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उत्तर
The working principle of the transformer is the mutual induction. The magnetic flux linked with the primary winding of the transformer must change, to produce an induced emf in the secondary coil.
Transformers cannot work on DC voltages. If a DC supply is given to the primary coil of a transformer, it produces a steady magnetic flux. So, no emf will be induced in the secondary coil.
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संबंधित प्रश्न
The teachers of Geeta’s school took the students on a study trip to a power generating station, located nearly 200 km away from the city. The teacher explained that electrical energy is transmitted over such a long distance to their city, in the form of alternating current (ac) raised to a high voltage. At the receiving end in the city, the voltage is reduced to operate the devices. As a result, the power loss is reduced. Geeta listened to the teacher and asked questions about how the ac is converted to a higher or lower voltage.
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3) Write two values each shown by the teachers and Geeta.
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