<P> Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation . It is a form of luminescence . In most cases , the emitted light has a longer wavelength , and therefore lower energy , than the absorbed radiation . The most striking example of fluorescence occurs when the absorbed radiation is in the ultraviolet region of the spectrum , and thus invisible to the human eye , while the emitted light is in the visible region , which gives the fluorescent substance a distinct color that can only be seen when exposed to UV light . Fluorescent materials cease to glow nearly immediately when the radiation source stops , unlike phosphorescence , where they continue to emit light for some time after . </P>
<P> Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation . It is a form of luminescence . In most cases , the emitted light has a longer wavelength , and therefore lower energy , than the absorbed radiation . The most striking example of fluorescence occurs when the absorbed radiation is in the ultraviolet region of the spectrum , and thus invisible to the human eye , while the emitted light is in the visible region , which gives the fluorescent substance a distinct color that can only be seen when exposed to UV light . Fluorescent materials cease to glow nearly immediately when the radiation source stops , unlike phosphorescence , where they continue to emit light for some time after . </P>
what is something that gives out light called
what is something that gives out light called
fluorescent
fluorescent