Electro Magnetic Induction And Alternating Currents Question 180
Question: A coil of inductive reactance $ 31,\Omega $ has a resistance of $ 8,\Omega $ . It is placed in series with a condenser of capacitive reactance $ 25,\Omega $ . The combination is connected to an a.c. source of 110 volt. The power factor of the circuit is
Options:
A) 0.64
B) 0.80
C) 0.33
D) 0.56
Show Answer
Answer:
Correct Answer: B
Solution:
- Power factor, $ \phi =\frac{R}{\sqrt{{{( \omega L-\frac{1}{\omega C} )}^{2}}+R^{2}}} $ $ =\frac{8}{\sqrt{{{(31-25)}^{2}}+8^{2}}}=\frac{8}{\sqrt{6^{2}+8^{2}}}=\frac{8}{10}=0.8 $
