- #1
Rectifier
Gold Member
- 313
- 4
The problem
I want to calculate ## |I_1| ##
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.
I want to calculate ## |I_1| ##
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.