Magnetic Effects Of Current Question 82
Question: A and B are two concentric circular conductors of centre O and carrying currents $ I_{1} $ and $ i_{2} $ as shown in the adjacent figure. If ratio of their radii is 1 : 2 and ratio of the flux densities at O due to A and B is 1 : 3, then the value of $ i_{1}/i_{2} $ is [KCET 2000]
Options:
A) $ \frac{1}{6} $
B) $ \frac{1}{4} $
C) $ \frac{1}{3} $
D) $ \frac{1}{2} $
Show Answer
Answer:
Correct Answer: A
Solution:
$ r_{1}:r_{2}=1:2 $ and $ B_{1}:B_{2}=1:3 $ We know that $ B=\frac{{\mu_{0}}}{4\pi }.\frac{2\pi ni}{r}\Rightarrow \frac{i_{1}}{i_{2}}=\frac{B_{1}r_{1}}{B_{2}r_{2}}=\frac{1\times 1}{3\times 2}=\frac{1}{6} $
BETA
