A loop of tinsel can be suspended in the air using electrostatic repulsion by a charged pie plate.
Tie the tinsel into a loop. It will then be a loop with two legs
sticking out the other side of the knot.
Glue or tape a Styrofoam cup into the middle of a aluminum pie
plate. Caution, solvent based glues will dissolve Styrofoam, if you
use glue, choose hot melt glue, or water based glue. Or use tape.
Attach a Styrofoam cup to the center of the aluminum plate.
To Do and Notice
Charge the styrofoam
Rub the Styrofoam with the wool. Rub firmly for at least 15 seconds.
Rub a Styrofoam block with a wool cloth.
Charge the pie plate
Place the aluminum pan on top of the charged Styrofoam plate. Use
the Styrofoam handle and be careful to avoid touching, or even
coming near any part of the pan with any part of your body.
Bring the tip of your finger close to the pan. When you are closer than a centimeter you should: hear a snap, feel a shock and &emdash; in dim light &emdash; see a spark.
Place the aluminum pan on the charged Styrofoam plate, bring your hand near the plate and feel the spark!
Hold the charged pie plate by the styrofoam in one hand, with the foam cup underneath the pie plate and the flat bottom of the pie plate pointing toward the ceiling. Hold the loop of tinsel in your other hand, near but not touching the pie plate, with the two "legs" toward the pie plate. Hold it about 10 cm away.
The tinsel will be attracted to the pie plate. Release the tinsel, it will jump toward the pie plate. Then jump away. Watch out! The tinsel will be attracted to your hand and your body, keep away from it! If it touches you it will lose its charge and you will not be able to fly it.
Hold the pie plate under the tinsel. The electrostatic repulsion will push up the tinsel and hold it in the air even though gravity is pulling it down.
Notice that the loop of tinsel opens up into a circle.
What's Going On?
When you rub the styrofoam with the wool it becomes negatively charged. (You can check this using the tape electroscope.) When you place the pie pan on the styrofoam and touch it the pie pan becomes positively charged.
The tinsel is attracted to the charged pie pan since charged things attract uncharged things by electrically polarizing them. That is, the near side of the tinsel becomes positively charged while the far side becomes negative. The attraction of the negative pie pan for the near, positive, side of the tinsel is weaker than the repulsion for the far, negative, side.
When the tinsel touches the pie pan, some of the charge from the pie pan is transferred to the tinsel so that both are positively charged. They then repel and you can use this repulsion to fly the tinsel.
The tinsel opens up into a circle since all of the positive charges on the conducting aluminum of the tinsel repel each other.
If you can get some of the thin flat pink plastic that Asian markets use to wrap packages you can make, and then fly, a "hydra." See the Snack, Flying Hydra.
See the book "Flying Tinsel" by Grant Mellor, June 1993, Addison Wesley
Scientific Explorations with Paul Doherty
25 May 2000