Electro Magnetic Induction And Alternating Currents Question 170
Question: A coil has resistance 30 ohm and inductive reactance 20 ohm at 50 Hz frequency If an ac source, of 200 volt, 100 Hz, is connected across the coil, the current in the coil will be
Options:
A) 4.0 A
B) 8.0 A
C) $ \frac{20}{\sqrt{13}},A $
D) 2.0 A
Show Answer
Answer:
Correct Answer: A
Solution:
-
If $ \omega =50\times 2\pi $
then $ \omega L=20\Omega $
If $ \omega ‘=100\times 2\pi $
then $ \omega ‘L=40\Omega $
Current flowing in the coil is $ I=\frac{200}{Z}=\frac{200}{\sqrt{R^{2}+{{(\omega ‘L)}^{2}}}}=\frac{200}{\sqrt{{{(30)}^{2}}+{{(40)}^{2}}}} $
