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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
A group of students while coming from the school noticed a box marked "Danger H.T. 2200 V" at a substation in the main street. They did not understand the utility of a such a high voltage, while they argued, the supply was only 220 V. They asked their teacher this question the next day. The teacher thought it to be an important question and therefore explained to the whole class.
Answer the following questions:
(i) What device is used to bring the high voltage down to low voltage of a.c. current and what is the principle of its working ?
(ii) Is it possible to use this device for bringing down the high dc voltage to the low voltage? Explain
(iii) Write the values displayed by the students and the teacher.
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Describe briefly and two energy losses, giving the reasons for their occurrence in actual transformers ?
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Explain why core of a transformer is always laminated.
