Magnetic Effects Of Current Question 98
Question: What should be the current in a circular coil of radius 5cm to annul $ B_{H}=5\times {{10}^{-5}}T $ [DCE 2001]
Options:
A) 0.4 A
B) 4 A
C) 40 A
D) 1 A
Show Answer
Answer:
Correct Answer: B
Solution:
$ B={{10}^{-7}}\frac{2\pi i}{r} $ ; according to question BH = B
$ \Rightarrow 5\times {{10}^{-5}}={{10}^{-7}}\times \frac{2\times 3.14\times i}{5\times {{10}^{-2}}}\Rightarrow i=4A $
BETA
