A 100 Ω resistance and a capacitor of 100 Ω reactance are connected in series across a 220 V source. When the capacitor is 50% charged, the peak value of the displacement current is
$z = \sqrt{R^2 + X_c^2} = \sqrt{100^2 + 100^2} = 100\sqrt{2}$
$i_{max} = \dfrac{V_{max}}{z} = \dfrac{220\sqrt{2}}{100\sqrt{2}} = 2.2$
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