Determination of the magnetic moment of a magnet by letting it fall through a conducting pipe

Abstract

A novel method is proposed to determine the magnetic moment of a magnet by studying its free-falling motion inside a non-ferromagnetic and conducting pipe. The dynamics of a neodymium magnet falling inside a pipe is tracked by using sound waves of a fixed frequency generated by one smartphone and detecting acoustic resonance in the pipe simultaneously by the other. This tracking technique leads to the measurement of the terminal velocity of the falling magnet, as the interaction between the magnet and the conducting pipe creates viscosity artificially. The result obtained is verified by studying torsional oscillations of the suspended magnet and conforms to the reported value in such a low-cost setup. The experiment is designed with concepts integrating the domains of general physics, electromagnetic induction, and acoustics.

Cited by in corpus (5)

• Study of the effect of electromagnetic damping force on a magnet oscillating near a non-ferromagnetic conducting plate
• A smartphone-based simple method for determination of the free space permeability
• Determining Viscosity of a Liquid with Smartphone Sensors: A Classroom-Friendly Approach Using Damped Oscillations
• Determination of the acceleration due to gravity by studying magnet s motion through a conducting pipe
• Demonstration of magnetic dipole-dipole interaction by using smartphone pressure sensor