GATE 2021 EE – Question 50
In the given circuit, for maximum power to be delivered to $R_L$, its value should be ________ $\Omega$. (Round off to 2 decimal places.)
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Correct answer: 1.40 to 1.42
Explanation
At $\omega=1$ krad/s the 4 mH inductor is $j4\ \Omega$ and the 0.5 mF capacitor is $-j2\ \Omega$, so the source branch has series impedance $j2\ \Omega$. In parallel with the $2\ \Omega$ resistor, $Z_{th}=\frac{2(j2)}{2+j2}=1+j\ \Omega$. For maximum power to a purely resistive load, $R_L=|Z_{th}|=\sqrt2=1.41\ \Omega$.