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In the circuit shown find (i) the current I (ii) V1 and V2 (iii) Pf. Draw the phasor diagram.
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Given:

(i) Current:

$X_{L1}=2\pi fL=2\pi \times 50\times 0.05=15.71\ \Omega \\ X_{L2}=2\pi f L=2\pi \times 50\times 0.1=31.42\ \Omega $

$X_C=\dfrac{1}{2\pi fC}=\dfrac{1}{2\pi \times 50\times 50\times 10^{-6}}=63.66\ \Omega $

$\bar Z=10+j15.71+20+j31.42-j63.66\\ \ \ \ =30-j16.53=34.25\lt -28.85^{\circ}\ \Omega $

$I=\dfrac{V}{Z}=\dfrac{200}{34.25}=5.84\ A$

(ii) V1 and V2 

Let,     $\bar I=5.84\lt 0^{\circ}\ A$

$\bar Z_1=10+j15.71=18.62\lt 57.52\ \Omega $

$\bar V_1=\bar Z_1\bar I=(18.62\lt 57.52^{\circ})(5.84\lt 0^{\circ})=108.74\lt 57.52^{\circ}\ V$

$\bar Z_2=20+j31.42-j63.66=20-j32.24=37.94\ \lt -58.19^{\circ}\ \Omega $

$\bar V_2=\bar Z_2\ \bar I=(37.94\lt -58.19^{\circ})(5.84\lt 0)=221.57\lt -58.19^{\circ}\ V$

(iii) Power Factor

$pf = cos\phi =cos(28.85^{\circ})=0.875\ (leading)$

(iv) Vector diagram

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