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Science Rocks!


Electroscope

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Sent in by:
Wendy of Atlanta, GA

Feeling static? Get charged!
Materials

Materials Needed


  • balloon
  • foam plate
  • foam cup
  • drinking straw
  • glue
  • aluminum pie pan
  • thread
  • aluminum foil
  • masking tape
  • wool scarf
  • comb
  • plastic ruler

Instructions

Instructions


  1. Check with an adult before you begin.
  2. In the ZOOMscis, Static Electricity, Electric Gelatin and Snap, Crackle, Jump, you can use static electricity to move different substances. Now, make an Electroscope to test the presence of static electricity in an object.
  3. Make two holes near the bottom of a Styrofoam cup on opposite sides.
  4. Push a plastic straw through the holes in the cup.
  5. Turn the cup upside down and glue it onto the bottom of an aluminum pie pan. Make sure that the cup is right at the edge so that the straw sticks out over it. If you don't want to wait for the glue to dry, tape the cup to the pan.
  6. Cut a piece of thread about 8 inches long and tie a few knots in one end of the thread.
  7. Cut a one-inch square of aluminum foil. Use it to make a ball around the knots in the thread. The ball should be about the size of a marble. It should be just tight enough so it doesn't fall off the thread.
  8. Tape the end of the thread to the straw so that the ball of foil hangs straight down from the straw, right next to the edge of the pan.
  9. Tape the straw to the cup so it doesn't move around when you use the Electroscope.
  10. To test the Electroscope, create some static electricity. An easy way to create static is by rubbing a balloon on a Styrofoam plate. When you do this, you "charge" the plate, which means you cause a buildup of electrons on one side. Even though the plate is charged, the electrons don't move because Styrofoam doesn't conduct electrons.
  11. Once you've created some static electricity, place the Electroscope on top of the Styrofoam plate. Be sure to hold the electroscope by the foam cup and not the aluminum pan, otherwise it won't work. Electrons move easily through metal, so when you put the pie pan onto the foam plate, the electrons travel into the pan and the foil ball. When the electroscope detects static electricity, the foil ball pushes out from the pan.
  12. Try charging different objects, like a comb or ruler, with static electricity. Test them on the Electroscope and compare your results. Which objects hold an electric charge? Which don't? Be sure to send your findings to ZOOM!


Are you charged up for the science scoop? Because electrons have a negative charge, the foil ball and the pie pan both become negatively charged after touching a staticky object. When two things have the same charge, they repel, or push away from one another, which is what the foil ball does when it moves away from the pie pan. If you put your finger towards the foil ball, the foil ball will move towards it. If you let the ball touch your finger, your finger takes electrons from the ball and the ball bounces back and forth between your finger and the pan. If you touch anything metal, like the pan or the foil ball, you'll pick up the charged electrons with your fingers. This is why you need to hold the Electroscope by the cup and not the pan.

Try adding more foil balls to your Electroscope or experiment with two Electroscopes at the same time. If you come up with any discoveries, send them to ZOOM.

Some of your Results

Daniela, age 8 of Baltimore wrote:
All of a sudden my experrament shocked everyone who toched it.

Garrett, age 9 of Baltimore, MD wrote:
How do you charge the objects to test the electroscope and then do you place the pie pan on the charged object? Having trouble getting this experiment to work!

Brandon, age 12 of New York, NY wrote:
I tested with tissue paper and wool for my science fair project and tissue paper ended up making more static electricity than the wool! If you dont have wool in your house, you can use tissue paper instead.

John, age 8 of Avon, OH wrote:
It was so cool! The ball kept bouncing from the plate to my finger! You a re cool!

Jose, age 10 of Hollywood, FL wrote:
Nothing! Also, how do you create static electricity with the other objects such as a copper penney, comb etc. I understand rubbing the ballon with a Styrofoam plate, but how can I create a charge with the other materials.

Amy, age 12 of Gold Coast, Australia wrote:
i tried it with 3 balls and the electric charge was very cool it bounced of the pie tine really fast

Olivia, age 10 of NY wrote:
at first, my project did not work. then I put my finger on the foil ball, then let go. this was the best project ever!

Giselle, age 11 of Surrey wrote:
It was so cool!! I tried it with my friend and it really worked. The strips do repel and I learned that if the strips fall back then its a negative charge, but if the strips spread way further then it's a positive! Well see ya!

Chelsea, age 14 of Harrisonburg, VA wrote:
OMG! this has to be the coolest project that I've ever done with ZOOM. When I was little I watched it allll the time and when I found out that we had to do the science fair I went right to your website and looked up cool things to do. Thank you guys!

Karina, age 13 of Chicago, IL wrote:
It Work!!! Yeah!!! Love the project. I need it for my science project. Thanks Zoom!!!

Vollie of Harrisonburg, VA wrote:
What happened when I did this was the aluminum foil ball flew off of the straw when I put the wool scarf against it. It was amazing!!

Jaeda, age 12 of Astoria, NY wrote:
I found out that the wool scarf worked better than the balloon. I think this is the coolest project ever.

Siera, age 12 of Woburn, MA wrote:
I tried 3 times and it did not work. Next I tried it with a wool scarf and it worked better than the balloon. I was so happy that it worked.

Kadejah, age 11 of Hopkins, SC wrote:
I seen that mostly the metal object had farther distance I wonder why.

Courtney, age 11 of Ontario, Canada wrote:
It was soo cool the ball actually moved left to right when did the experiment. And I used for my science project and my teacher gave me an A+ because I was the only one who did static electricity.

Gregory, age 15 of Compton, CA wrote:
It worked great!! I acually made the electroscope three times and each time I made one, I changed at least one material. Some worked and some didn't.

Kenya, age 12 of Phoenix, AZ wrote:
What it happened to me was that I did not have a wool scarf. Insted I us a balloon and it work ver well and got a A+.

Lexus, age 10 of Milwaukee, WI wrote:
Well, first it didn't work. I was so mad becuse the science fair was right around the corner, but when the science fair came I was playing with the Electroscope and discoered that if you put your fingers kind of clase to the sides of the ball that it moves. I got an A+!

Gracie of Farmington, MI wrote:
We are studing eletrictiy in school and we did the same experiment but we used a pith ball instead of a foil one. When we rubbed it with the wool it didn't work so well. The thing that worked best for us was a classmates fleece sweater. Our homework was to answer some questions about the experiment. Some of the answers I didn't know I found on the Zoom website. It really helped.

Chelsy, age 10 of Canada, PE wrote:
I tryed it first with a wool skarf but that did not work at all but hen I tryed it with a balloon and it worked great just how it was supost to and I tryed rubbing a baloon on a wool skarf then putting the tin pan on and it worked. I did it for y scince fair and evryone loved it.

Dala, age 11 of Collinwood, TN wrote:
The ball didn't go out as far as I thought it would, but when I touched it it bounced back just like you said it would.

Hannah, age 10 of Stanfield, NC wrote:
When I did the electroscope project I measured the amount of static each item produced by timing how long it took the electroscope to stop moving.

Kayla, age 8 of Plymouth, MN wrote:
When I tested my Electroscope my mom and I felt some sort of a magnet holding it down. I got a shock when I picked it up, too.

Elyse, age 11 of Greenwich, CT wrote:
I didnt have a stirafoam cup so I used a plastic one but when I did the experement it worked, the ball of aluminum foil stayed away from the pan.

Meghan, age 12 of Bloomingdale, NJ wrote:
When I did this expirement I didn't have an aluminum pie pan so I made one myself. It didn't work as well as I thought it would because the aluminum ball didn't go out as much, but as you did in the show when Mike touched the foil ball and it went back and forth between his finger and the pan. I tried that out and it worked so I guess the aluminum ball did extend a little from the pan. I used this ZOOMsci for a How-2 book report for school. I hope everybody in my class liked it.

Meredith, age 11 of Cookeville, TN wrote:
I tryed it with a plastic cup instead and it worked great the aluminum ball did not come out as far maybe only a mm but when I put my finger to it it worked like you said it would.

Ash, age 12 of Penetanguishene, ON wrote:
I saw how ZOOM made an eletroscope an I thought it was super cool. I am doing an eletroscope for my science project, I made it a bit differently though. I made my structure out of legos an then I hung 3 balls of foil to it. I tried it workes great, way good with the ballon!

Susie, age 12 of NY wrote:
IT was so amazing, it actually worked. The foil ball moved away about 4 inches! Im going to use it for a science project.

Tanisha, age 12 of Hartford, CT wrote:
Well at fist when I tried the electroscope some of the objects I used didnt work like the plastic ruler. But when I tried the aluminium foil it made static electricity and a lot of it too. So after all at the end it worked out well.

Mariem, age 11 of Stamford, CT wrote:
When I did the electroscope it was preety cool. At first I used the more sturdy one but it didn't work that well because the electrons probably didn't have much room to travel.


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