Home > Resources for our Science Kits > Science Projects for Kids > 3D Electric Field Viewing Bottle

3D Electric Field Viewing Bottle

- William Beaty

Maybe you've heard of magnetic fields, but did you know that there is another kind of field? It's called an electric field, e-field, electrostatic field, or voltage-field. An electric field exists around any object having an imbalance of electric charge.

When you rub a balloon on your arm and then use the balloon to make your arm hair stand on end, the imbalanced charge remains on your hairs and on the balloon's surface. What reaches out from the surfaces and makes the hairs stand up? An electric field!

You can use tiny pieces of hair to make an Electric Field Viewing Bottle. When exposed to static electricity, the pieces of hair will align themselves in electric fields, revealing the shape of the field patterns.

                ______
               ||    ||
               ||____||
         ___-----    -----___
        /               |    \
        |         _      \   |
        |    --__   \        |
       |              \  \    |
       |     -              \ |        
       |      __       ---___ |      _______________
       |                  __  | \   /  CHARGED COMB  \
       |   ___--       ---    | --> I||||||||||||||||I
       |        __--       /  | /   I||||||||||||||||I
       |   _           /      |
       |  /               /   |
       |       /             |
        |      |         |   |   The floating fibers make the
        |            |       |   electric field visible
         \__________________/
                BOTTLE

Materials:

plastic comb or blown-up balloon
straight, black hair (either artificial or human; you can use hair from an old Halloween mask or doll)
plastic bottle full of baby oil with paper label on only one side, or a removable label if on both sides
scissors

Optional:

rubbing alcohol to remove label
pan or shallow dish for the alcohol
white spray-paint (optional)

Procedure

Remove the Label

If your oil bottle has labels on both sides, peel the label from one side by picking at it with your fingernails while running it under warm water.
An easier way is to soak one side of the bottle in a shallow dish of rubbing alcohol for about 10 or 15 minutes, and then peel the label off.
Use a bit of alcohol and a paper towel to clean off the remaining glue.
You can improve your bottle by removing all labels and painting one side of the bottle with white spray paint. This gives you a smooth white background against which to view the floating dark fibers.

Cut the Hair into Small Pieces

Gather a hank of hair and use the scissors to trim it straight across.
Repeatedly cut across the hank of hair to make strips narrower than 1/8", as small as 1/16" if you can. This will give you thousands of short hair fibers.
Fill a measuring teaspoon with hair fibers. If you use a really tiny bottle of baby oil, use less than a teaspoon of fibers.
Note: If you use too many fibers, they will clump and settle to the bottom of the bottle too fast. If you use too few, they will be difficult to see.

Mix the Hair Fibers into the Oil

Gently wad up the hair fibers.
Drop the wad into the bottle of baby oil.

Experiment with Your 3D Electric Field Viewer

Hint:

Cap the bottle securely and shake it until the wad of hair fibers is spread evenly throughout the oil.
Note: It's best to shake the bottle with a violent rotating wrist motion rather than just shaking straight up and down. Up-and-down shaking only works if there is a large bubble.
While the fibers are still mixed into the oil, charge your plastic comb by combing your hair with it, or rub the balloon on your hair, then hold the charged comb or balloon near the bottle. You'll see the fibers slowly line up with the spreading field created by the charged comb or balloon.
Note: As usual, this type of charging by contact (friction) only works when the humidity in the room is low.
As the hairs start to settle to the bottom, shake the bottle to continue experimenting.

Used with permission of Bill Beaty.

For more field-viewing fun, try the 3D Magnetic Field Viewing Bottle project.

Be sure to check out our Science Fair Project Books and Kits too. You'll find plenty of exciting projects and ideas for budding young scientists.

Home > Resources for our Science Kits > Science Projects for Kids > 3D Electric Field Viewing Bottle

DiscoverThis Science Kits and Toys is upfront