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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
Name two kind of energy loss in a transformer. How is it minimized?
Describe, with the help of a suitable diagram, the working principle of a step-up transformer. Obtain the relation between input and output voltages in terms of the number of turns of primary and secondary windings and the currents in the input and output circuits.
The input and output voltages of a transformer are 220 V and 44V respectively. Find the current in input circuit if the output current is 2 A.
Distinguish between Step up and Step Down Transformer.
Transformer works on ______.
What are step-up and step-down transformers?
Assertion: A transfonner cannot work on D.C. supply.
Reason: D.C. changes neither in magnitude nor in direction.
Read the following paragraph and answer the question:
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.
If the secondary coil has a greater number of turns than the primary, ______.
Two coils P and Q are kept near each other. When no current flows through coil P and current increase in coil Q at the rate 10A/s, the emf in coil P is 15mV. When coil Q carries no current and current of 1. 8A flows through coil P, the magnetic flux linked with the coil Q is ______.
A 12 V, 60 W lamp is connected to a 220 V AC supply using an ideal transformer. Find the primary current.
