Question

The magnetic field on the axis of a circular loop of radius $100 \,cm$ carrying current $I=\sqrt{2} A$, at point $1\, m$ away from the centre of the loop is given by:

• A. $3.14 \times 10^{-7} T$
• B. $6.28 \times 10^{-7} T$
• C. $3.14 \times 10^{-4} T$
• D. $6.28 \times 10^{-4} T$

Answer 1

Answer: (A)

$B _{ A }= B _0 \sin ^3 \theta$
$=\frac{\mu_0 i }{2 R } \times \sin ^3 \theta$
$=\frac{4 \pi \times 10^{-7} \times \sqrt{2}}{2 \times 1} \times\left(\frac{1}{2 \sqrt{2}}\right)$
$B _{ A }=3.14 \times 10^{-7} T$