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प्रश्न
Explain the construction of transformer.
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उत्तर
Principle:
The principle of a transformer is the mutual induction between two coils. That is, when an electric current passing through a coil changes with time, an emf is induced in the neighbouring coil.
Construction of transformer
Construction:
- In the simple construction of transformers, there are two coils of high mutual inductance wound over the same transformer core.
- The core is generally laminated and is made up of a good magnetic material like silicon steel. Coils are electrically insulated but magnetically linked via transformer core.
- The coil across which alternating voltage is applied is called primary coil P and the coil from which output power is drawn out is called secondary coil S.
- The assembled core and coils are kept in a container which is filled with suitable medium for better insulation and cooling purpose.
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संबंधित प्रश्न
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Long distance power transmissions
The large-scale transmission and distribution of electrical energy over long distances is done with the use of transformers. The voltage output of the generator is stepped up. It is then transmitted over long distances to an area sub-station near the consumers. There the voltage is stepped down. It is further stepped down at distributing sub-stations and utility poles before a power supply of 240 V reaches our homes.
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A transformer is essentially an a.c. device. It cannot work on d.c. It changes alternating voltages or currents. It does not affect the frequency of a.c. It is based on the phenomenon of mutual induction. A transformer essentially consists of two coils of insulated copper wire having different numbers of turns and wound on the same soft iron core.
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- power is transmitted at 220 V. Comment on the feasibility of doing this.
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