Final answer:
The three main emission lines of a mixed gas KrAr laser are centered around 568.2 nm, 647.1 nm, and 676.4 nm, signifying the precise wavelengths where light is emitted due to the energy transitions of krypton and argon atoms.
Step-by-step explanation:
The three main emission lines of a mixed gas KrAr laser are typically centered around the wavelengths of 568.2 nm (yellow-green), 647.1 nm (red), and 676.4 nm (also red). Each emission line represents a narrow wavelength band where light is emitted due to transitions between specific energy levels of the krypton (Kr) and argon (Ar) atoms. These lines occur when an electric discharge excites the atoms in the gas mixture, and the resulting photons are released as the excited electrons return to their ground states.
Emission lines are crucial in understanding the properties of light emitted by gaseous substances and are used in various applications, including spectroscopy and laser technologies. The specificity of these emission lines makes KrAr lasers valuable for tasks requiring precise wavelength control.