# A series LR circuit is connected to an ac source of frequency w and the inductive reactance is equal to 2R. A capacitance of capacitive reactance equal to R is added in series with L and R. The ratio of the new power factor to the old one is :

Question:

A series LR circuit is connected to an ac source of frequency $\omega$ and the inductive reactance is equal to $2 R$. A capacitance of capacitive reactance equal to $R$ is added in series with $\mathrm{L}$ and $\mathrm{R}$. The ratio of the new power factor to the old one is :

1. $\sqrt{\frac{2}{3}}$

2. $\sqrt{\frac{2}{5}}$

3. $\sqrt{\frac{3}{2}}$

4. $\sqrt{\frac{5}{2}}$

Correct Option: 4

JEE Main Previous Year 1 Question of JEE Main from Physics Alternating Current chapter.
JEE Main Previous Year Online April 25, 2013

Solution:

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