Fluorescent Light Science Experiment

Learn how to make a fluorescent light glow without plugging it in! These science experiments show how to generate static electricity, which illuminates the phosphor coating, making the bulb light up.

Fluorescent Light Experiment Materials

• Fluorescent bulb (tubes work best. It's okay if the light is burnt out.)

Any of the following:

• Saran wrap (plastic wrap)
• Plastic report folder
• Piece of wool
• Inflated balloon
• Dry newspaper
• Animal fur or fake fur

Procedure

1. The fluorescent light needs to be perfectly dry, so you may wish to clean the bulb with a dry paper towel before starting. You will get brighter light in dry weather than in high humidity.
2. All you need to do is rub the fluorescent bulb with the plastic, fabric, fur, or balloon. Do not apply pressure. You need friction to make the project work; you don't need to press the material into the bulb. Don't expect the light to be as bright as it would be plugged into an outlet. It helps to turn off the lights to see the effect.
3. Repeat the experiment with other items on the list. Try other materials found around the home, classroom, or lab. Which works the best? Which materials don't work?

How It Works

Rubbing the glass tube generates static electricity. Although there is less static electricity than the amount of electricity supplied by wall current, it is enough to energize the atoms inside the tube, changing them from a ground state to an excited state. The excited atoms release photons when they return to the ground state. This is fluorescence. Usually, these photons are in the ultraviolet range, so fluorescent bulbs have an interior coating that absorbs the UV light and releases energy in the visible light spectrum.

Safety

Fluorescent bulbs are easily broken, producing sharp shards of glass and releasing toxic mercury vapor into the air. Avoid applying a lot of pressure to the bulb. Accidents happen, so if you snap a bulb or drop one, put on a pair of disposable plastic gloves, carefully use damp paper towels to collect all the pieces and dust, and place the gloves and broken glass in a sealable plastic bag. Some places have special collection sites for broken fluorescent tubes, so see if one is available/required before putting the bulb in the trash. Wash your hands with soap and water after handling a broken fluorescent tube.