At-Home Science — To Float a Paperclip

  by Erik Wolgemuth

You’ll need a bit of finesse and perseverance with this experiment because odds are you’ll have to give this one a few attempts before you pull it off perfectly. No worries, it will work and a failed attempt or two along the way will allow for an appropriate character lesson on perseverance along with a brief biographical lesson or two about Edison’s repeated inventing failures or Jordan’s inability as a sophomore to make the varsity high school basketball team.

What we’re doing here is playing with the surface tension of water and, in the process, you’ll be floating a paperclip (find the smallest one you can…you’ll have better success with a small size). Before your effort at floatation occurs, it’s a good idea to allow your kids opportunity to try to float the paperclip on their own. After a few sunken attempts, which will convince them of the impossibility of what you’re about to attempt, change things up a bit. Snag a square of two-ply toilet paper. (If your toilet paper is singular in its ply, my condolences and sympathies.) Separate the plies so you’re just using one, tear off a bit and drop a small square into the water, then rest your paperclip on top. Supported by the ply of toilet paper, your paperclip will sit on the surface, but now it’s time to utilize your dormant Operation skills to carefully sink the ply of paper from underneath the paperclip, which should remain on the surface of the water. A sharp #2 pencil is a good choice as the sinking instrument; just take your time pushing the paper down slowly, bit by bit. Again, it might take a few attempts, but eventually you’ll be able to sink the paper, leaving just the paperclip on the surface.

The trick here is tapping into water’s surface tension. You can explain it in the context of an inflated balloon or perhaps, a tastier illustrative route, Jello. If you were to touch either with something pointed, like a fork, the balloon pops/the Jello is pierced. Whatever tension and strength existed on the surface was breached. However, if you changed how the fork met the surface of the balloon or Jello, the surface tension holds and the fork remains on top. So it is with water’s surface tension as well. A simplistic explanation of surface tension perhaps, but one that should make sense to those little minds.

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We’ve got a few other at-home science experiments to suggest: ice fishing, penny cleaning, and the ol’ baking soda and vinegar volcano. Making cupcakes is also kind of scientific, if you think about it.

Photo by Chrissy Wolgemuth; used by permission. Amazon links are affiliate links.