Can you create a tiny spark that works the same way as a lightning bolt? Lightning happens when a huge buildup of electric charge jumps between clouds and the ground. You can make that same jump happen on a small scale.
You push a thumbtack through an aluminum pie plate and attach a pen as a handle. Rub a piece of styrofoam with a wool sock to build up a negative charge. Then use the pen to set the pie plate on the charged styrofoam.
Turn off the lights and slowly bring your finger toward the edge of the plate. A small spark jumps from the plate to your fingertip. You can see it and hear it.
Hypothesis
The hypothesis is that rubbing the styrofoam with the wool sock will create a negative charge that will repel electrons on the pie plate.
A huge buildup of charge can jump between objects as a spark, the same way lightning jumps between clouds and the ground. You rub styrofoam with a wool sock to build charge on the foam. Then you set an aluminum pie plate on top. When your finger gets close to the plate, a small spark jumps to your fingertip.
Electric charge pushes and pulls on nearby objects. Rubbing styrofoam with a wool sock builds up negative charge on the surface. When you bring your finger close to a charged pie plate, that charge jumps across the gap as a spark.
Rubbing styrofoam with a wool sock transfers charge from one surface to the other — the friction leaves the styrofoam with a strong negative charge. When you set an aluminum pie plate on top using a pen handle, that charge repels electrons on the plate's surface. The imbalance builds until, in a darkened room, a small visible spark jumps from the plate's edge to your fingertip.
A huge buildup of electric charge causes lightning when it jumps between clouds and the ground. You can trigger that same discharge on a small scale. Rubbing styrofoam quickly with a wool sock creates a negative charge that repels electrons on the pie plate. Turn out the lights and slowly bring your finger close to the pie plate. A small spark jumps from the plate to your fingertip, one you can see and hear.
Method & Materials
You will push the thumb tack up through the centre of the pie plate, push the end of the pen onto the tack, rub the styrofoam quickly with the wool sock, pick up the aluminum pie plate with the pen and put it down on top of the styrofoam, and turn out the lights and slowly bring your finger close to the pie plate.
You will need an aluminum pie plate, ball-point pen, thumb tack, wool sock, and piece of styrofoam.
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When you bring your finger close to the edge of the plate, the repelled electrons jump across the gap and escape through your body, giving you a small shock. When you turn off the lights, you should be able to see (as well as hear and feel) the discharge.
Why do this project?
This science project is so interesting and unique because it allows you to create your own miniature version of a lightning bolt with just a few simple materials.
Also Consider
Experiment variations to consider include using different materials to create the negative charge, such as a balloon or a comb, and using different materials for the pie plate, such as copper or glass.
Full project details
Additional information and source material for this project are available below.
