Magnetic Effects Of Current Question 422
Question: Two wires are wrapped over a wooden cylinder to form two coaxial loops a carrying current $ i_{1} $ and $ i_{2} $ . If $ i_{2}=8i_{1} $ the value of x for B = 0 at the origin O is:
Options:
A) $ \sqrt{(\sqrt{7}}-1)R $
B) $ \sqrt{5}R $
C) $ \sqrt{3}R $
D) $ \sqrt{7}R $
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Answer:
Correct Answer: D
Solution:
[d] Magnetic field on axis of circular coil is $ \frac{{\mu_{0}}iR^{2}}{2{{(R^{2}+x^{2})}^{3/2}}}=\frac{{\mu_{0}}iR^{2}}{2{{(R^{2}+x^{2})}^{3/2}}}=\frac{{\mu_{0}}i_{2}R^{2}}{2{{(R^{2}+x^{2})}^{3/2}}} $ $ x=\sqrt{7}R $
BETA
