First slide

Phasors and Phasor Diagrams

Question

Power factor of a $L - R$ series circuit is 0.8. When a capacitor is connected in series with R and L, the power factor increases to unity. Then reactance of the capacitor is

Moderate

A

$\frac{3 R}{4}$
B

$\frac{2 R}{3}$
C

$\frac{R}{2}$
D

$\frac{R}{4}$

Solution

$\frac{R}{\sqrt{R^{2} + X_{L}^{2}}} = 0.8 \Rightarrow X_{L} = \frac{3 R}{4}$
Again, $\frac{R}{\sqrt{R^{2} + {(X_{L} - X_{C})}^{2}}} = 1 \Rightarrow X_{C} = X_{L}$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App