1 For severe stains, add 1-2 cups vinegar to the wash cycle as well. 2  To remove a rust stain from your cotton work clothes, moisten the spot with some full-strength vinegar and then rub in a bit of salt. 3  If itâs warm outdoors, let it dry in the sunlight (otherwise a sunny window will do), then toss it in the wash.
absorption spectrum - the spectrum of electromagnetic radiation that has passed through a medium that absorbed radiation of certain wavelengths. spectrum - an ordered array of the components of an emission or wave.
Astronomers can learn a lot about distant objects by analyzing spectra. The 3 types of spectra are continuous, emission, and absorption. A continuous spectrum comes from a high pressure blackbody, or thermal source (such as a light bulb). An emission spectrum has bright lines. It is caused by cool, low-pressure gas.