The magnetic field at the center of the circular loop as shown in figure, when a single wire is bent to form a circular loop and also extends to form straight sections, is

Magnetic field due to 'AB';B→1=μ0I4πRsinπ2-sinπ4⊗=μ0I4πR1-12⊗ Magnetic field due to circular loop, B→2=μ0I2R⊙ Magnetic field due to straight wire BC B→3=μ0I4πRsinπ2+sinπ4⊙=μ0I4πR1+12⊙ B→=B→1+B→2+B→3 =μ0I2R+2μ0I4πR12⊙=μ0I2R1+12π⊙