A uniform circular wire loop is connected to the terminals of a battery. The magnetic field induction at the centre due to $A B C$ portion of the wire will be (length of $A B C=l_1$, length of $A D C=l_2$ )

213724-q

  • A

    $\frac{\mu_0}{2 R} \frac{i l_1 l_2}{\left(l_1+l_2\right)^2}$

  • B

    $\frac{\mu_0}{2 \pi R^2} \frac{i l_2}{\left(l_1+l_2\right)}$

  • C

    $\frac{\mu_0}{2 R} \frac{i\left(l_1+l_2\right)}{l_1 l_2}$

  • D

    Zero

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