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प्रश्न
How is the e.m.f. across primary and secondary coils of a transformer related with the number of turns of the coil in them?
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उत्तर
`E_S/E_P = N_S/N_P`
Here e.m.f. is directly propotional to number of turns.
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संबंधित प्रश्न
A transformer converts 240 V AC to 60 V AC. The secondary has 75 turns. The number of turns in primary are _______.
(A) 600
(B) 500
(C) 400
(D) 300
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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
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Which of the following statement is true?
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The value of current in the bulb is ______.
Name one electrical device which works on Faraday's law of electromagnetic induction principle.
The primary winding of a transformer has 100 turns and its secondary winding has 200 turns. The primary is connected to an a.c supply of 120 V and the current flowing in its is 10 A. The voltage and the current in the secondary are ______.
A transformer is used ______
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