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प्रश्न
An a.c generator generates an emf 'ε' where ε = 314 Sin (50πt) volt. Calculate the frequency of emf ε.
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उत्तर
Since e = 314 sin 50 πt V
∴ ω = 50 π
Hence, frequency, f = `(50pi)/(2pi)` = 25 Hz or Rad s-1
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संबंधित प्रश्न
State the principle on which transformer works.
Derive an expression for e.m.f. and current in terms of turns ratio
Mention various energy losses in transformer device
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(ii) Explain in brief, its working.
(iii) What material is used for the core of an electric bell? State the reason.
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.
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- Lower current implies less power loss.
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The primary coil having NP turns of an ideal transformer is supplied with an alternating voltage VP. Obtain an expression for the voltage VS induced in its secondary coil having NS turns.
