When the towel no longer drips, weigh it on a kitchen scale. You can heap up the towel on the scale rather than neatly folding it. Record the mass on a piece of paper. Fold an identical paper towel in three if it was not already prefolded and fold it one more time so six layers of towel are on top of one another.
Wet it thoroughly and hang it—still folded—so all of the excess water drips out. Do you think this folded paper towel holds more, less or just as much water as the unfolded paper towel? When the folded towel stops dripping, weigh it on a kitchen scale. Do not unfold it; place it on the scale then read and record its mass.
Does it weigh more, less or exactly the same as the wet unfolded paper towel? If there is a difference, why do you think the mass is different? Now that you measured how much water the folded and unfolded paper towels can hold, and maybe found a difference, which do you think would dry your hands better?
Place a fresh, unfolded paper towel and an identical fresh paper towel folded in three in a dry spot on your workspace. Wet your hands, shake them three times to remove most of the water and then dry them off with the unfolded paper towel.
Do your hands feel completely dry, somewhat dry or still quite wet? Repeat wetting and shaking your hands. Try to shake your hands in the same way you did the first time then dry them with the folded paper towel. How do your hands feel now? Do they feel dryer, wetter or just as dry as when you used the unfolded paper towel? If your hands feel very dry with both the folded and unfolded paper towels, try again with half a paper towel, as follows: Cut a paper towel in half and dry your hands with an unfolded half-towel and with a folded half-towel.
Do you feel a difference now? How can your findings help you use fewer paper towels for the same job? Extra: If you have more paper towels of the same type, repeat the tests; perform each step exactly the same way and notice the variations in the outcomes.
Does the measured difference in mass vary a lot or just a bit? Is it always the folded or always the unfolded paper towel that weighs more? Do your hands always feel drier when using the folded or the unfolded paper towel? Scientists repeat tests to verify the outcome. Scientists also like to have their studies repeated by a different researcher utilizing different instrumentation such as the scale. If the independent tests reveal the same results, the test is called reproducible.
Incidentally, this wonderful solubility of water in cellulose is also what causes shrinkage and wrinkling in cotton clothing when you launder it. The cotton draws in water so effectively that the cotton fibers swell considerably when wet and this swelling reshapes the garment.
Hot drying chases the water out of the fibers quickly and the forces between water and cellulose molecules tend to compress the fibers as they dry. The clothes shrink and wrinkle in the process. Can shampoo increase hair loss? Thank you. Your name. Leave this field blank. Support Us!
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