By shining light through the water and carefully observing what happens, you gain important insights about haze in air. The haze unit uses a number of different light sources and detectors. In this activity, you investigate a photoresistor and get a feel for how light detectors operate. The detector used in the haze experiment is not very sensitive to light, so you will need to amplify its output. This activity shows how to do this with a simple electronic circuit that uses an important kind of chip, called an operational amplifier, or opamp.
Light consists of different colors that can be separated out into a spectrum.
In this activity, you will create a spectrum and find out how different materials and detectors respond to the different colors.