Question

ABCDA is an amperian loop, $\oint \overrightarrow{B}.\overrightarrow{dl}$ along the loop is

• A. $56\pi \times {10}^{-7}$
• B. zero
• C. $28\pi \times {10}^{-7}$
• D. $11\pi \times {10}^{-7}$

Answer 1

The correct option is B zero

$\oint \overrightarrow{B}.\overrightarrow{dl}={\mu }_0\left\{i_{enclosed}\right\}$
$={\mu }_0\{3+4+5-5-7\}$
$={\mu }_0\left(0\right)=0$