A square current loop of side 1/√2 m carries current 5 A. The magnetic field at its centre, in μT, is:

Question

G1 Physics · Accepted Answer

For one side, B=μ₀I/(4πr)(sin45°+sin45°), with r=a/2=1/(2√2) m. Four identical sides contribute. Substituting I=5 A gives B=8×10⁻⁶ T=8 μT.