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].

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…

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…

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…

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.

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…

The use of smartphones in experimental physics is by now widely accepted and documented. PASCO scientific's smart cart, in combination with student-owned smartphones and free apps, has opened up a new universe of low-cost experiments that have traditionally required cumbersome and expensive equipment. In this paper we demonstrate the simplicity,…

This paper reports on the measurement of a magnetic field due to the coil carrying current by using the magnetic sensor in a smartphone as an alternate to the relatively expensive magnetic sensor probe. The location of the magnetic sensor in the smartphone was known by mapping the value of the magnetic field due to the permanent magnetic bar so…

A magnetic linear accelerator (or Gauss accelerator) is a device that uses the conversion of magnetic energy into kinetic energy to launch an object with high velocity. A simple experimental implementation consists of a line of steel spheres in which the first one is a permanent magnetic sphere. If another steel ball collides with the magnetic…

The spatial dependence of magnetic fields in simple configurations is a common topic in introductory electromagnetism lessons, both in high school and in university courses. In typical experiments, magnetic fields and distances are obtained taking point-by-point values using a Hall sensor and a ruler, respectively. Here, we show how to take…

We provide a design for a low cost orientable search coil that can be used to investigate the variation of magnetic flux with angle. This experiment is one of the required practical activities in the current A level physics specification for the AQA examination board in the UK. We demonstrate its performance and suggest other suitable…

The concept of curved space is not readily observable in everyday life. The educational movie "Sphereland" attempts to illuminate the idea. The main character, a hexagon, has to go to great lengths to prove that her world is in fact curved. We present an experiment that demonstrates a new way to determine if a two-dimensional surface,…

We have developed a laboratory exercise designed to help students translate between different field representations. It starts with students qualitatively mapping field lines for various bar magnet configurations and continues with a Hall probe experiment in which students execute a series of scaffolded tasks, culminating in the prediction and…

The damped oscillator is discussed in every high school textbook or introductory physics course, and a large number of papers are devoted to it in physics didactics journals. Papers typically focus on kinematic and dynamic aspects and less often on energy. Among the latter, some are devoted to the peculiar decreasing behavior of energy…