Assembling a magnetometer for measuring the magnetic propertiesof iron oxide microparticles in the classroom laboratory

A compact magnetometer, simple enough to be assembled and used by physics instructional laboratory students, is presented. The assembled magnetometer can measure the magnetic response of materials due to an applied field generated by permanent magnets. Along with the permanent magnets, the magnetometer consists of two Hall effect-based sensors, a wall-adapter dc power supply to bias the sensors, a handheld digital voltmeter, and a plastic ruler. Here, a project-based exercise is described, where the objectives are as follows: (i) assemble the magnetometer, (ii) measure the magnetic response of the iron oxide microparticle sample, and (iii) obtain the magnetization of the sample from the measurements.