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Science Rocks!

Pennies And Water


your results

Sent in by:
Katherine of Grapevine, TX

Fill it to the rim, and then some.

Materials Needed

  • glass
  • pitcher of water
  • pennies
  • liquids of different thicknesses like oil, syrup or juice
  • paper and pencil



  1. Check with an adult before you begin.
  2. In the ZOOMsci, Drops on Pennies II, you can test how many drops of different liquids the surface of a penny can hold. Now, test how many pennies a glass of each liquid can hold before spilling.
  3. Predict how many pennies you think you can put in a full glass of water without letting any leak over the edges.
  4. Make a chart for your predictions and results. Write the names of each liquid you will test in rows on the left side of your paper. Write "predictions" and "results" in columns along the top of your paper. Record your prediction for how many pennies the glass of water will hold.
  5. Fill a glass with water to the top. Make sure the rim of the glass is dry, so that water won't drip down.
  6. Count the pennies as you add them to the water. See how far you can get the water to bulge over the edge of the glass without leaking down the edges.
  7. Record the number of pennies the water could hold before the surface tension was broken.
  8. Compare your prediction with your result. Is one number higher than the other? If so, why do you think they are different? Now, use the results from testing the glass of water to make some predictions about the other liquids you are testing.
  9. Record your predictions on your chart.
  10. Fill a glass with whichever liquid you are testing. Make sure that the rim is dry before you begin.
  11. Count the pennies as you add them to the glass. Record how many pennies the glass held before spilling the liquid over the edge.
  12. Compare the results you get for each liquid. Do you see a pattern? Do some types of liquid hold more pennies than others? Be sure to send your discoveries to ZOOM.

Can your brain hold the science scoop without overflowing? The pennies take up space in the glass, and the liquid has to get out of the way to make room for the pennies. The only way the liquid can get out of the way is to go up. It doesn't overflow right away because the surface of the liquid sticks together really well. This is called surface tension.
Can you think of other ways to experiment with surface tension? send your ideas and results to ZOOM.

Some of your Results

Angel, age 10 of Middletown wrote:
in the water there were 90 and in the vinegar there were 148! can you belive that!

ZOOM Fan wrote:
the vinegar had the most pennies.

Abby, age 13 of Turner, ME wrote:
I did this for a school project and I got 76 pennies and 9 dimes and nickels into the cup of water. I got 77 pennies into a cup of cooking oil. The only hard part was cleaning the pennies after they had been in the oil. Also if you are using oil you might want to do it over a sink because when it does go over it is really hard to pick up!

Jennell, age 13 of Ontario wrote:
It became shiny.

Tianna, age 11 of Toronto, ON wrote:
i but a penny in coke for a few weeks and it looks bran new

Brooke, age 9 of Rogers, TX wrote:
they sunk

Brittany, age 12 of Pensacola, FL wrote:
i was so suprise I thought that the water would only hold 3 pennies but I was totally wrong it held 13 pennies i thougt that oil would hold 10 pennies but it held 15 i thought that maple syrup would hold 13 pennies boy was I wrong it held 26 pennies my sister is doing this experiment and she is getting way different answers than me so I guess it depends on the force you drop it in. I fyou get different answers than some of the people are posting I guess results may very

Jackie, age 12 of Cantonment, FL wrote:
i used water oil and syrup for my project i estimated that the oil would hold 10 pennies and it held 69!!! maybe I was droping them to lightly! for water I estamated 15 pennies and I got 17. and for the syrup I estamated 30 pennies and got 29 to fit before it started to go over the side! this is a verry neat expirement and you should try it!!!

Herbert of Cullman, AL wrote:
when I i a penny my dad gave it to me and when he did I test it out I came up to this much of water on the penny 235 drops then at the 236 drop it titted over

Meghan, age 8 of Seekonk, MA wrote:
I thought it was only going to take 10 pennies in water but it took 125!! It took 100 pennies in maple syrup! This was fun!!

Ella, age 9 of Fulton, NY wrote:
I could fit 50 drops of water on one penny.

Jonnell, age 12 of Riviera Beach, FL wrote:
The water only took 32 pennies, the orange juice only took 30 and the maple syrup took 42 pennies1 This experiment was very exciting and fun I hope to do more like these thanks alot zoom!!! I

Sierra, age 9 of Salt Lake City, UT wrote:
The pennies did not drop straight down. They went down at an angle.

Archer, age 10 of Orillia, ON wrote:
I did it and it took me 54 pennies before it spilled.

Christina, age 8 of Endicott, NY wrote:
The water held more pennies than the Apple Juice and the Dawn Dishwashing Soap.

Jake, age 10 of Hoover, AL wrote:
It took 67 before mine over flowed.

Emily, age 9 of Jamaica, NY wrote:
When I did this experiment with my mom we were surprised to find out that canola oil had a greater surface tension than mapel syrup.

Nikilesh, age 6 of North Wales, PA wrote:
The water needed 30 pennies to overflow. But, the orange juice just needed 11 pennies to overflow.

Sunpreet, age 11 of Mission, TX wrote:
Instead of pennies I used marbles. So I put in 26 marbles and it over flew!!

Jasmine wrote:
I got 150 before it over filled.

Maria, age 10 of East Quogue wrote:
For the water, I predicted 25 pennies. It was actually, 41 pennies. For the full glass, I predicted 35 and it was over 41 pennies.

Aashi, age 6 of Seattle, WA wrote:
I was able to put in 95 pennies before it overflowed.

Jameshia, age 11 of Birmingham, AL wrote:
Well it took 59 pennies to make the water go up withoil.

Bailey, age 9 of Kansas City, MO wrote:
Every one over floaded. The thicker the liquid is the more it holds. The thinner the liquid is the less it holds.

Haley, age 8 of Tamarac, FL wrote:
Well it took 100 pennys to make the water go you to the top.

Jonathan, age 6 of Baltimore, MD wrote:
Orange juice took 3 pennies but water took 4 pennies.

Tiffany, age 11 of Oakland, CA wrote:
It took 95 pennies, 31 dimes, and 53 nickels to fill to the rim.

Ashleigh, age 10 of Greenfield, MA wrote:
Well I first put water in a plastic cup. Then I put pennies in. I put in 2, 876 pennies before the water spilled all over the table.

Brittany, age 15 of Newfoundland wrote:
I put my pennies in the water and it could hold 42 pennies wow I was surprised u guys have some kewl experiments.

Maria, age 11 of Boston, MA wrote:
At my School, in science class we did this experiment. I found out that in a 5. 5 inch cup you can fit about 50 if not more pennies in the cup, befor it over flows. It might of happened because of the cohesion of water, or the gravity of the penny. Thats what migh of made it over Flow. But all in all I really liked this project and wish to do it again.

not yet implemented