Question
What is a transformer? Write down its working principle and construction.
✓
Answer
→The device using which alternating voltage can be changed from one to another of greater or smaller value, is called a transformer.
• Principle :
→Electro magnetic induction (Mutual induction)
• Construction :
→A transformer consists of two sets of coils, insulated from each other. They are wound on a soft iron core, either on top of the other as in fig. (a) or on separate limbs of the core as shown in (b).
→One of the coils is called the primary coil and the other is called the secondary coil.
→Number of turns in the coils are $N _{ P }$ and $N _{ S }$ respectively.
→Often, the primary coil is the input coil and the secondary coil is the output coil of the transformer.
→When an alternating voltage is increased using a transformer, it is called step up transformer, and if the voltage is decreased, the transformer is known as step down transformer.
• Principle :
→Electro magnetic induction (Mutual induction)
• Construction :
→A transformer consists of two sets of coils, insulated from each other. They are wound on a soft iron core, either on top of the other as in fig. (a) or on separate limbs of the core as shown in (b).
→One of the coils is called the primary coil and the other is called the secondary coil.
→Number of turns in the coils are $N _{ P }$ and $N _{ S }$ respectively.
→Often, the primary coil is the input coil and the secondary coil is the output coil of the transformer.
→When an alternating voltage is increased using a transformer, it is called step up transformer, and if the voltage is decreased, the transformer is known as step down transformer.
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