JEE Mains · Physics · STD 12 -7. Alternating current
For the series LCR circuit connected with 220 V , 50 Hz a.c source as shown in the figure, the power factor is \(\frac{\alpha}{10}\). The value of \(\alpha\) is _________
- A 4
- B 10
- C 6
- D 8
Answer & Solution
Correct Answer
(C) 6
Step-by-step Solution
Detailed explanation
Power factor \( =\frac{R}{Z} \) \( Z=\sqrt{R^{2}+(X_{L}-X_{C})^{2}} \) \( =\sqrt{60^{2}+(150-70)^{2}}=100\Omega \) ∴ Power factor \(=\frac{60}{100}=\frac{6}{10}\) Then \( a=6 \)
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