I am Watching YOU!! Light The Electromagnetic Spectrum Increasing Energy Energy of Light 10−6eV 10−4eV 1− 2eV 40eV KeV MeV Energy to ionize atom or molecule: 10-1000eV Where does light actually come from? Light comes from the acceleration of charges. Accelerating Charges Oscillating Charges Radio & Microwave Frequency of EM wave is the same as the frequency of oscillation. How is Infrared Light made? Light comes from the acceleration of charges. Thermal Excitation: f ~ T Incandescence Color shifts to shorter wavelengths (higher frequency) as an object is heated. increasing temperature How is Visible Light made? Light comes from the acceleration of charges.