Two conducting rings of radii r and 2r move in opposite directions with speeds 2v and v respectively on a conducting surface in a uniform magnetic field B perpendicular to the plane. The potential difference between the highest points of the two rings is:

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 8rvB EMI and AC.