The Weakest Link

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The Weakest Link

• Ann Smith
• Mrs. Hunt 8th Period
• Science Fair Project
• February 2007

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Abstract
Introduce topic Tell what experiment
did Results Conclusion

• Paper towels are important because everyone uses
  them. People always get frustrated when paper
  towels break in their hands. This experiment
  tested the strengths of four different brands of
  paper towels. The strengths of Bounty, Scott,
  Brawny, and Wal-Mart brand paper towels was
  tested by determining how many hex nuts each held
  when wet without breaking. Bounty held the most
  with an average of 179 hex nuts. Wal-Mart held
  the least with an average of 62 hex nuts. This
  difference does not support the idea that Brawny,
  the paper towel with the circular design, is the
  strongest. Instead, these results show that
  Bounty, with the diamond design , is the
  strongest of the paper towels tested.

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Problem

• Which paper towel is strongest when wet?

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Hypothesis

• The paper towel with the circular design is
  strongest when wet.

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Materials

• 3 Scott Paper Towels
• 3 Bounty Paper Towels
• 3 Brawny Paper Towels
• 3 Wal-Mart Paper Towels
• Rubber Band
• Bucket (16½ cm opening)
• 5 ml of Water (x12)
• Graduated Cylinder
• 250 ½ inch Hex Nuts

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Procedures

• Put the paper towel over the bucket opening and
  secure with rubber band. Gently pull paper towel
  tight.
• Measure 5ml of water into graduated cylinder and
  pour it evenly across the paper towel. Turn
  bucket to spread evenly.
• Carefully place hex nuts, one at a time, onto
  paper towel. Continue until the hex nuts fall
  into the bucket.
• Repeat steps 1-3 three times with each brand of
  paper towel.

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Procedures (cont.)

• 5.

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Controlled Variables

• Spread water evenly
• Paper towels are pulled tight
• Amount of water (5 ml)
• Same type/size of rubber band
• Type of hex nut (½ inch)
• Opening of bucket (16½ cm)
• Used whole paper towel
• Set hex nut down gently

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Manipulated Variable

• The brand of paper towel
• Scott
• Bounty
• Brawny
• Wal-Mart

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Responding Variable

• The number of hex nuts needed to break the wet
  paper towel

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Results

• How Many Hex Nuts Can a Wet Paper Towel Hold?

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Results (continued)

• How Many Hex Nuts Can a Wet Paper Towel Hold?

Number of Hex Nuts
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Results (cont.)

• How Many Hex Nuts Can a Wet Paper Towel Hold?

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Conclusion

• The results of these tests do not support the
  hypothesis. The paper towel with the circular
  design was not the strongest. The range of the
  results was 62 hex nuts held by Wal-Mart brand
  paper towels compared to 179 hex nuts held by
  Bounty paper towels. The paper towel with the
  diamond design, Bounty, was the strongest.
  Further testing could be done to find out how the
  paper towels perform under different uses such as
  window cleaning and absorbing liquids.

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Background (Research)

• Paper towels get their strength from plant fibers
  in cellulose. Cellulose is the cell walls of the
  bark from trees. Cellulose gives plant cells
  their shape, holds them together, and gives them
  durability.
• People often equate higher prices with better
  quality. The prices of the paper towels tested
  in this experiment were Bounty, 75 cents per
  roll Scott, 72 cents per roll Brawny, 62 cents
  per roll and Wal-Mart, 48 cents per roll.

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Works Cited

• Kramer, Eric. How are paper towels made?
  MadSci Network. 1997. Washington University
  Medical School. 15 Oct. 2003 http//madsci.org/pos
  ts/archives/dec97/880215232.Ot.r.html.
• Wal-Mart. Wade Hampton Blvd. Greenville, SC. 15
  Oct. 2003.