Finer points of the stopping power formula and the range of its validity are shown. Bremsstrahlung, or braking radiation, occurs when charged particles change direction. Energy loss mechanisms and their relative strengths are defined in simple ratios. The upper and lower ranges of validity for the stopping power formula are shown. Cyclotrons and synchrotrons, accelerators which make use of charged particle beams, are explained. The EDS (elemental dispersive x-ray spectroscopy) spectra from electron microscopes are also explained, for how to use charged particle beams to identify elements.