The potential differences across the resistance, capacitance and inductance are $80 \mathrm{~V}, 40

Question

The potential differences across the resistance, capacitance and inductance are $80 \mathrm{~V}, 40 \mathrm{~V}$ and 100 V respectively in an $L-C-R$ circuit. The power factor of this circuit is\

Professor PC Thomas Classes · Answer

(c): Here, $V_{R}=80 \mathrm{~V}, V_{C}=40 \mathrm{~V}, V_{L}=100 \mathrm{~V}$ Power factor, $\cos \phi==\frac{R}{Z} \quad=\frac{V_{R}}{V}=\frac{V_{R}}{\sqrt{V_{R}^{2}+\left(V_{L}-V_{C}\right)^{2}}}$ $$ =\frac{80}{\sqrt{(80)^{2}+(100-40)^{2}}}=\frac{80}{100}=0.8 $$