Complex currents and voltages - current in a branch

AI Thread Summary
The discussion revolves around calculating the current |I_1| in a circuit involving complex impedances. The user attempts to derive |I_1| using the total impedance Z_total, which includes resistive and reactive components. However, the user expresses concern that their result does not match the expected answer, which omits the capacitor's impedance. Other participants agree that the provided answer seems questionable, as it lacks consideration for the capacitor's influence. The conversation highlights the importance of accurately incorporating all circuit elements in impedance calculations.
Rectifier
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The problem
I want to calculate ## |I_1| ##

RCMQMNp.jpg


The attempt

## V_m = Z_{total}I_1 \\ I_1 = \frac{V_m}{Z_{total}} ##

## Z_{total} = \frac{ \frac{1}{jwC }\cdot (R + jwL) }{\frac{1}{jwC} + R + jwL} \\ \frac{ R + jwL }{1 + jwCR + jwCjwL} \\ \frac{ R + jwL }{1 - w^2LC + jwCR } \\ ##

## I_1 = \frac{V_m}{Z_{total}} = \frac{V_m}{\frac{ R + jwL }{1 - w^2LC + jwCR }} \\ = \frac{V_m(1 - w^2LC + jwCR)}{R + jwL} ##

## I_1 = \frac{V_m(1 - w^2LC + jwCR)}{R + jwL} \\ |I_1| = \frac{|V_m(1 - w^2LC + jwCR)|}{\sqrt{R^2 + (wL)^2}} ##

This does not look right since the answer is ## \frac{R|V_m|}{R^2 + (wL)^2} ##

Please help me.
 
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The given answer looks very suspicious since it doesn't include the capacitor impedance in any way. Your result looks okay to me.
 
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