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Question
Explain the construction of transformer.
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Solution
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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