Different kinds of lights

Do the activity Colors #2 in the manual.

Here are some pictures of some standard kinds of lights photographed through a diffraction grating (The colors of the spectra don't quite match what you will see -- when we talk about color, it will become clearer how a picture of a spectrum differs from a spectrum -- and width of the spectra also won't match -- but the pattern of bright lines will be the same).

Spectrum and name Source Comment
Hot wire glows when electricity
passes through it
The common light bulb
Mercury vapor light with fluorescent stuff, to make a more balanced spectrum
Electricity causes gas in tube and coating on tube to glow.
Color balance somewhat similar to daylight. Much more energy efficient than incandescent. Lighting for schools, stores
Compact fluorescent
Different fluorescent stuff, same idea as mercury lamp Efficient, color balance more similar to daylight.  Screw base means it can replace incandescent light bulbs

Neon discharge
Similar to mercury, but with a different gas inside Once very common in advertising signs (bright orange-red)

In addition to recording your survey of the different kinds of lights you find, you should write a note to yourselves about the experimental problems you may have encountered. Return to the sample page