Question 173 of 190

Primary coil of a transformer is connected to $220VAC$. Primary and secondary turns of the transforms are $100$ and $10$ respectively. Secondary coil of transformer is connected to two series resistances as shown in figure. The output voltage $\left({V}_{0}\right)$ is :

A$7V$B$15V$C$44V$D$22V$

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Answer: (A) $7V$

Ratio of EMF developed will be given by,
$\dfrac{{\epsilon }_{p}}{{\epsilon }_{s}}=\dfrac{{N}_{p}}{{N}_{s}}=\dfrac{100}{10} \Rightarrow {\epsilon }_{s}=22V$
Therefore, current in secondary circuit will be
$I=\dfrac{22}{22\times {10}^{3}}=1mA$
Hence, potential drop across $7k\Omega$ will be ${V}_{0}=I\times 7k\Omega =7V$