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.
A high-resolution spectrum of the Sun shows many, many, MANY dark absorption lines: Absorption lines are based on the same physical principle as emission lines: they involve an atom jumping from one particular energy level to another.In this case, however, the jumps must be upwards, from a low level to a higher one.ow-density clouds of gas floating in space will emit emission lines if they are excited by energy from nearby stars. Planetary nebulae, for example, are the remnants of stars which have gently pushed their outer envelopes outwards into space. Some of them are very pretty: