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Science Rocks!

Paper Clip and Keys


your results

Sent in by:
Amanda of Portage, MI

A paper clip with a speedy clip!

Materials Needed

  • four keys
  • paper clip
  • one meter of string



  1. Tie the keys to one end of the string.
  2. Next, tie the paper clip to the other end of the string.
  3. Put the string over your finger so that the keys hang straight down, just a few centimeters.
  4. Hold the paper clip with your other hand.
  5. Then, let go of the paper clip. What happens?
  6. Because the keys weigh more than the paper clip, the paper clip gets pulled forward pretty fast by the falling keys. But no matter how fast the paper clip is going forward, it also has to fall downward because of gravity. Then it keeps going until it wraps around your finger.

See what happens when you try this trick using objects that have very different weights or using different kinds of string, like yarn or fishing line. Send any discoveries that you make to the ZOOMsci feedback area.

Some of your Results

Tyler, age 10 of CT wrote:
it rapped around my finger then landed.

Sarah of MA wrote:
I don't understand. Am I supossed to tie something to my finger? Nothing happens.

Karson, age 10 of Winnipeg, MB wrote:
The heavier the objects we added to the string the faster the paper clip moved. It was great. We tried a lot of different objects with a lot of different weights.

Juan, age 9 of Boca Raton, FL wrote:
I forgot to tie the string to my finger. I will try it but this time I will do it right.

Asuka, age 8 of Suzhou wrote:
I tried the experimence with more keys and the paper clip went around my finger even faster. I used ten keys and it was so fast!!!

Yishai, age 11 of Washington DC wrote:
I tried it wild four keys and it worked but then I used twenty-five keys and the string broke but it was cool!!!

Kennith, age 10 of Bronx, NY wrote:
It really worked!!! I tried alot of keys and it went faster.

Keri, age 6 of TX wrote:
The paper clips rose without the magnet touching it.

Catherine, Kathleen of Braintree, MA wrote:
When we let go of the paper clip, it moves fast, and swung quivkly around our fingers. We used four keys and a big paper clip and it worked perfectly. When we added more keys it moved faster.

Taylor, age 11 of Nashville, TN wrote:
The paper clip stuck to the keys but wasn't strong enought to hold all the keys.

Walter, age 7 of Hollywood, FL wrote:
My mom and I tried it with a shoe string and 4 keys it worked great. It wrapped around my finger just like you said.

Lisa, age 8 of Laval, Montreal, QC wrote:
I used yarn instead of string and I found that it twirled faster and it rolled around my finger more times.

Tatenesha, age 11 of Reaford, NC wrote:
When I did it and let go of the clip it twirfled around my finger and fell off because instead of using string I used twain. It was so cool!!!

Jenn, age 14 of Pincourt, QC wrote:
I let go of the paper clip, and it wrapped around my finger, then sort of flew off my finger, it was sooo cool!!!

Jennifer of Westlake Village, CA wrote:
When I let go of the paper clip the string just unwound once but it did it very very slow. I think my problem was the string beacause I couldn't find regular string so I used nitting string I think that was my problem.

Jackson, Wyatt, Jessica, age 9 of ON wrote:
We did your experiment with the string, paperclip, and keys. We used cotton knitting string for the experiment. The experiment worked but the string slipped off of our finger and the keys hit the ground.

Dallas, age 6 of Lumsden, SK wrote:
It worked very fast and you guys were right - the more weight, the more faster it goes!

Paige, age 12 of Tucson, AZ wrote:
I used yarn and then instead of using a paper clip I used chalk. And it worked.

Zachery, age 10 of Helena, AL wrote:
You said to try this experiment with yarn and I did. It worked the same as yours did with the string. That was cool!!!

Laura, age 13 of Parsippany wrote:
It twirled around my fingers, but I also tried a different way to find out would happen. I did the same thing but used a top of a soda can and dropped the keys with my pointer under the string. The keys were so heavy for the little top that it hit my finger as if to twirl, but bounced right off. I also tried using different amounts of fingers. It worked with 2 fingers, 3 fingers, and something really cool happened with 4. Get this... it only worked with 4/5 fingers when the string was leveled with the ring fingers middle knuckle. Pretty cool, huh?

Erica, age 12 of Versailles, IN wrote:
I used one meter of string and a paper clip. I also used four keys, but each time I did it, I took off one key until I only had one key left. They all worked but when I used one key it went very slow around my finger. I also tried to make the string shorter. I made it one foot long and since there was not alot of string it didn't work.

Emily, age 11 wrote:
I use a paper clip and a key chain. With dental floss it did not work because the floss was to sticky.

Vanessa, age 10 of Rochester, NY wrote:
When I put a baby rattle on one side of the yarn and a papper clip on the other the papperclip still wound only it didn't hold.

Sarah, age 5 of Memphis, TN wrote:
I used string, but first we had to measure one meter of string. First we tried 4 keys and a paper clip. It twisted around my mom's finger. I tried it and it twisted around my finger too. Next we tried a screwdriver instead of keys. And it did the same thing. It spun around my mom's finger one way, then spun back around the other way and fell to the floor. Then last we tried a toy giraffe. And it worked! The end.

Amy, age 8 of Centennial, CO wrote:
I used yarn, it did not work because the yarn was to thick, the paperclip went down with the keys.

Trina, age 6 of Hartselle, AL wrote:
I used yarn, my mom's keys, and a paper clip. When I turned loose of the paper clip the keys dropped and the yarn twisted around my mom's finger. It was cool!!

Joe, age 12 of Woodbrigde, VA wrote:
The paper clip was a big 1 so it took all 4 keys to pull it down.

Evan, age 4 of Milford, NH wrote:
My dad tried it several times. The string wrapped around his finger, but then it just unwrapped and the keys fell to the floor. Removing keys didn't help. We experimented more and discovered that it wasn't wrapping around his finger enough times to stay up. So then we tried my finger, which is smaller (I had to stand on a table to be tall enough). This time it worked! Maybe a longer string would work for a grownup.

Lizzie, age 12 of TX wrote:
Everybody in my class had to find an experiment to do. One person in our class did this and we all agreed it was the best! I tried doing it afterward and I thought it was a lot of fun and really cool!

Kiara, age 14 of Tn wrote:
I never knew that paper clips and keys could do that. So what I want to say is I love your show. Oh ya thank for helping me do my work.

James, age 7 of Newtown, CT wrote:
My brother and I tried it with yarn and it worked too! Then we tried the yarn with a beanie baby and that worked also and then we tried a glove and it worked! It was fun experimenting.

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