The model illustrates the operation of a mass spectrometer used for analysis of chemical composition. The unknown ions are accelerated by an electric field and pass through the grid into a region of uniform magnetic field. There the ions travel along circles determined by their Larmor radii and arrive at various points on a position sensitive detector. In the model you can change the velocity at which the ion passes through the grid before entering the region of magnetic field (i.e. the speed to which the ion is accelerated by the electric field). Also you can change the value of uniform magnetic field and see how it influences on the trajectory of ions? motion. You are required to investigate different pairs of known ions using mass spectrometer. Then try to determine what the unknown ions are using Larmor radii. Try different values of the magnetic field and make sure that your results don?t depend on the field magnitude.