Alternating Current

JEE Main level, numerical answer, medium

180 of 190

Question 180 of 190

A common transistor radio set requires 12V12V (D.C.)\left(D.C.\right) for its operation. The D.C.D.C. source is constructed by using a transformer and a rectifier circuit, which are operated at 220V220V (A.C.)\left(A.C.\right) on standard domestic A.C.A.C. supply. The number of turns of secondary coil are 24,24, then the number of turns of primary are

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Answer: 440

NPNS=VPVS\dfrac{{N}_{P}}{{N}_{S}}=\dfrac{{V}_{P}}{{V}_{S}}
NP24=22012\dfrac{{N}_{P}}{24}=\dfrac{220}{12}
NP=220×2412{N}_{P}=\dfrac{220\times 24}{12}
NP=440{N}_{P}=440

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