The Relationship Between Toilet Paper Ply and Strength
Grade Level: 3rd to 8th; Type: Physics
This project investigates the relationship between strength and one, two, and three-ply toilet paper.
- How does the ply-number of toilet paper correlate to its strength?
- Is there a great difference in the strength of 1-ply and 3-ply toilet paper?
Toilet paper with more layers, or ply, is more expensive. Is the cost really worth the difference when it comes to the strength of the toilet paper?
- 1, 2, & 3-ply toilet paper
- Soup can
- Rubber band
- Roll out three sections of each type of toilet paper.
- Observe the paper’s thickness, softness, and texture.
- Position the 1-ply piece so that the middle section is covering the top of the can. The perforated lines and the other 2 sections should be on each side of the can.
- Place the rubber band around the can to hold the paper in place.
- Use the dropper to wet the middle of the bridged section of paper with 0.6 mL of water.
- Begin placing pennies on the dampened section one at a time.
- Continue placing the pennies until the paper breaks and the pennies fall into the can.
- Record your data.
- Repeat the experiment using the 2-ply and 3-ply paper.
- Analyze your data. Which ply of toilet paper held the most pennies before breaking? How does the number of pennies held correlate to the strength of the paper? Is there a relationship between the ply number and the strength? Do you think the texture of the paper affects the strength?
Terms/Concepts: strength, ply
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