|MadSci Network: Physics|
It seems like just a couple of days ago I was talking to my 13 year old brother about how to test the strength of paper towels for a school project. The paper companies test the strength of the paper towels with a couple of different methods that would be hard to do at home. There are a couple of simple experiments that can be done to test the paper towels. If you want to compare the strength of different types of paper towels, you could cut the paper into strips about 1 inch wide and 10 inches long and hold each end on top of soup can or something else that will hold the paper off the table. Then you can stack something like quarters or small weights until the paper towel breaks. By doing this, you can compare the dry strength of different brands of paper towels by counting how many quarters it takes to break the strip. A very important property of paper towels is known as wet strength. This is the ability of the paper to resist breaking when it is wet. There is a big difference between paper towels when they are wet and toilet paper when it is wet. You don't want your paper towel to fall apart when you wipe something up. You can test the wet strength in the same way you tested the dry strength, but before you stack the weights, pour a small amount of water (maybe 1 ounce) onto the middle of the strip. It might take a little bit of experimentation to get the right amount of water, but it should work well. As for the presentation, you can show bar graphs of how much each paper towel holds. It will be very easy to show which is strongest. I hope this helps with the project.
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