The question of whether Faraday's flux law is universal or whether there are exceptions has long been controversial. This discussion seemed to have recently concluded in favor of the generality of Faraday's Flux Law. The present article raises this question again with the aid of some rather simple measurements carried out on a Faraday generator.…

The question of how the processes around the Faraday generator with its rotating magnet should be interpreted has been controversial since its discovery by Faraday. Does the magnetic field rotate together with the rotating magnet or does it remain stationary? Furthermore, does one only need Faraday's flux law to interpret inductive processes, or…

A smartphone magnetometer is used to record the magnetic field of a freely falling point dipole magnet. The recorded magnetic field vs. time data are analyzed in accordance with the spatial dependence of the magnetic field to calculate the acceleration due to gravity g. The experiment gives local g to be 9.79 ± 1.9% m/s[superscript 2].

In this experiment, students explore the synthesis and physical property characterization of the magnetic material strontium hexaferrite (SrFe[subscript 12]O[subscript 19]). SrFe[subscript 12]O[subscript 19] crystallites are prepared by a simple but fascinating sol-gel autocombustion synthesis. The prepared powder is compacted into pellets and…

In physics lessons at secondary school and experimental physics courses at universities, the magnetic field inside a current-carrying solenoid is considered quantitatively. The corresponding equations and theories are supported by measuring the magnetic flux density inside the solenoid with a Hall probe. It has already been shown that smartphones…

Science and engineering students in the second semester of a calculus-based physics sequence typically study and measure the on-axis magnetic field for a multiple, circular turn coil. There are four benefits to this approach: 1) an analytical solution is easily obtained, 2) the coil is easily constructed using tightly wound, high-gauge wire where…

In a 1993 book review, E. Pearlstein asks, "Why don't textbook authors begin their discussion of magnetism by talking about magnets? That's what students have experience with." A similar question can be asked, "Why don't professors have students measure the force between permanent magnets in introductory physics labs?" The…

An alternative way of introducing magnetism at all levels of education is proposed. It is stressed that magnetism can be introduced through the interaction between current-carrying conductors giving the students, at the same time, the possibility to measure the magnetic permeability [mu][subscript o]. Focusing on currents instead of permanent…

The article presents the results of an experimental study on the motion of a neodymium magnet on an inclined duralumin plate. During experiments, the time of motion was measured, and the steady-state velocity of the magnet motion was determined. To measure the time, a robotic set was used, which made it possible to measure the time of the motion…

All physics is fascinating, but some stories are more exciting than others. A story that involves some of the most precise measurements ever made and a tantalizing discrepancy might be one of the most interesting. Throw in a 3200-mile journey, a heavily laden truck covered by a tarpaulin, closed-down highways with police escorts, and hushed…

Interaction forces between magnetic fields and current loops play a central role in the theory of magnetism. This work describes a reasonably simple and cheap experiment for demonstrating this issue: the force on a thin coil due to a nearby cylindrical magnet. The magnitude of the force as well as its attractive/repulsive character is comfortably…

There have been a few methods described in this journal and elsewhere for measuring the wavelength of the standing electromagnetic waves in a microwave oven. Typically, these involve melting chocolate, cheese, or some other substance on a plate that is prevented from rotating. In this article I describe a more dynamic and colorful technique that…

Measuring the "e/m" ratio is a classic experiment in the physics curriculum. We show that smartphones can reliably measure the magnetic field strengths involved. Moreover, phone cameras and the image-processing software Tracker can make determining the charge-to-mass ratio of the electron more accurate.

With the wide availability of strong neodymium magnets, the slow and stately fall of a magnet through a conducting pipe has become a favorite classroom demo for teaching electromagnetic induction, Newton's third law, and Lenz's law. Since Lenz's law is conceptually difficult for some students, several authors have used this demo to explore in…

Measuring magnetic induction is occasionally performed by our students during their academic training in physics. Among the various methods used to measure it, the Hall effect is the most common and widespread. Another way consists of employing an electronic flux-meter. It is constituted by a small flat coil (SFC) connected to the input of an…