An infinitely long straight conductor is bent into the shape as shown below. It carries a current of i Amps, and the circular loop is R meters. Then the magnitude of magnetic induction at the center of the circular loop is :

Question

 

$(1)\; \frac{\mu_o i}{2 \pi R} \\(2)\;\frac{\mu_o n i}{2  R} \\ (3)\; \frac{\mu_o i}{2 \pi R}(\pi +1) \\(4)\; \frac{\mu_o i}{2 \pi R}(\pi-1)$