Question

A current of $2A$ is flowing through a circular coil of radius $10cm$ containing $100$ turns. The magnetic flux density at the centre of the coil is (in $Wb/m^2$ )

• A. $0.126\times {10}^{-2}$
• B. $1.26\times {10}^{-2}$
• C. $1.26\times {10}^{-4}$
• D. $1.26\times {10}^{-5}$

Answer 1

Answer: (A)

$0.126\times {10}^{-2}$

$B=\frac{n{\mu }_{0}i}{2r}$
$=\frac{100\times 2\pi \times {10}^{-7}\times 2}{10\times {10}^{-2}}$
$=0\cdot 126\times {10}^{-2}T$