Complex currents and voltages - current in a branch

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SUMMARY

The discussion focuses on calculating the current |I_1| in a branch of an electrical circuit using complex impedance. The user attempts to derive |I_1| using the formula I_1 = V_m / Z_total, where Z_total is calculated based on the components R, L, and C. The user expresses concern that the provided answer, which is R|V_m|/(R^2 + (wL)^2), does not account for the capacitor's impedance. The community confirms that the user's derivation appears correct and highlights the importance of including all components in the impedance calculation.

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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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