Physics - EMI/AC Question with Solution | TestHub

At very high frequencies, inductor acts as an open circuit and capacitor as short circuit.

So, capacitive reactance, $X_C=\frac{1}{\omega \mathrm{C}}\approx 0$

Also, inductive reactance, $X_L=\omega L\approx \infty$

Thus, equivalent circuit can be redrawn as

Here, both $4\Omega$ resistances are in parallel and together they are in series with$1\Omega$ and $2\Omega$ resistances.

Equivalent impedance is $Z=1+\frac{4\times 4}{4+4}+2=5\Omega$

Effective current is $I=\frac{220\mathrm{V}}{5\Omega }=44\mathrm{A}$