Which one of the following options represents the magnetic field B⃗ at O due to the current flowing in the given wire segments lying on the xy plane?

Question

G1 Physics · Accepted Answer

Add the fields at O from each straight segment using B=μ₀I(sinθ₁+sinθ₂)/(4πr), with sign from the right-hand rule. The collinear/radial pieces contribute zero. The remaining segments sum to B⃗=-(μ₀I/L)[1+1/(4√2π)]k̂. Hence C.