Two infinite parallel wires separated by distance d carry equal currents I in opposite directions, with dI/dt=2 A s⁻¹. A square loop of side d lies in the same plane as shown. For d=2π m, if the induced emf is nµ₀ln4/3 volt, find n.

Question

G1 Physics · Accepted Answer

Magnetic flux is Φ=∫B⃗·dA⃗ and induced emf is ε=-dΦ/dt. Apply Lenz’s law for direction and I=ε/R when the circuit is resistive. This gives 2.