Easy INTEGER +4 / -1 PYQ · JEE Mains 2021

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

Answer (integer) 440

Solution

In a transformer,<br/><br/>${{{N_p}} \over {{N_s}}} = {{{V_p}} \over {{V_s}}}$<br/><br/>where, N<sub>p</sub> = number of turns in primary circuit, N<sub>s</sub> = number of turns in secondary circuit = 24, V<sub>p</sub> = potential of primary circuit = 220 V and V<sub>s</sub> = potential of secondary circuit = 12 V<br/><br/>$\Rightarrow {{{N_p}} \over {24}} = {{220} \over {12}}$<br/><br/>$\Rightarrow {N_p} = 440$

About this question

Subject: Physics · Chapter: Alternating Current · Topic: AC Circuits: R, L, C

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