Ampère's law for specially designed axially symmetric steady currents: an educational perspective

Abstract Application of Ampère's law by employing symmetry is one of the most efficient approaches for solving problems in magnetostatics. However, previous research shows that students face difficulties in recognizing and applying the symmetry arguments, particularly in complex and non-ideal situations. One way to address this challenge is to broaden a set of problems involving Ampère's law and symmetry, and design adequate experimental setups pertinent to these problems, which can be relatively simply reproduced. Here we present one such problem where Ampère's law can be used to calculate the solution, with a related experimental setup and properly designed set of measurements. In addition, we validate the solution by showing it obeys equations of magnetostatics with appropriate boundary conditions involving surface currents and discontinuities in the magnetic field, which provides deeper understanding of the underlying physics.