Mass Spectrometry

Mass spectrometers are workhorse instruments for modern chemical analysis, including forensics, toxicology and even space exploration. This activity consists of two demonstrations to illustrate the basic working principle of mass spectrometry, the deflection or “bending” of charged particles in a magnetic field. In Part A, dropping a magnet through a metal tube demonstrates the formation of eddy currents and provides evidence for the interrelationship of electric and magnetic fields. Thus, a moving charge creates a magnetic field, and a moving magnet or changing magnetic field also induces an electric current. In Part B, a model mass spectrometer simulation, steel spheres representing charged particles follow a curved path when they roll past a magnet.