Two identical wires `A and B` , each of length 'l', carry the same current `I`. Wire A is bent into a circle of radius `R and wire B` is bent to form a square of side 'a' . If ` B_(A) and B_(B)` are the values of magnetic field at the centres of the circle and square respectively , then the ratio `(B_(A))/(B_(B))` is :

Options

A. `(pir^(2))/(16sqrt(2))`
B. `(pi^(2))/(16)`
C. `(pi^(2))/(8sqrt(2))`
D. `(pi^(2))/(8)`

Answer

C