Question

For loop $ABCDA$, $\oint \overrightarrow{B}.\overrightarrow{di}$ will be?

• A. equals to $4{\mu }_0$
• B. greater than $4{\mu }_0$
• C. less than $4{\mu }_0$
• D. None of the above

Answer 1

The correct option is C less than $4{\mu }_0$

$\oint \overrightarrow{B}.d\overrightarrow{i}={\mu }_0(i_c+i_d)$
$={\mu }_0(i_c+{ϵ}_0\frac{d\varphi E}{dt})$
$={\mu }_0(8-1-3+(-ve\left)\right)$
$={\mu }_0(4-ve)$
$<{\mu }_0\left(4\right)$
$i_c$ = Conducting current
$i_d$ = displacement current