Though not as big or as long lasting as hurricanes, tornadoes are still pound-for-pound the most destructive force on Earth. They bring naught but unbelievably high-speed winds to the party, and can easily plow through anything that gets in their path. Those mighty, swirling winds form a vortex as they go, but with all the havoc they wreak, it can be difficult for the average Joe to get a good look at that well-known funnel-like form.
This handy dandy Demo Science science demo makes it easy for your students to see just what a vortex looks like and how the materials in that vortex move. Let’s take this one for a spin!
Make That 2 Bottles
For this experiment, you’ll need two two-liter soda bottles (no, one four-liter bottle will not work, Kevin!) with their caps, an electric drill and 1/2” drill bit, some duct tape, a little caulk (that’s c-a-u-l-k caulk, wiseguy), water, food coloring, and plastic confetti (or similar).
First things first, empty your soda bottles in whatever manner you see fit. Drink ‘em at home, bring ‘em in for the students to share (don’t give any to Kevin—his mom insists he’s “allergic” to sugar), pour ‘em down the drain, whatever. Just empty those suckers, then rinse ‘em clean and dry the outsides—the insides can still be wet.
Drill a hole in the center of each bottle cap, then stack them up back-to-back (top-to-top?) and seal the outer edge with a bead of caulk. Whatever you do, don’t eat caulk—you’ll just get sticky goo all over your face. Let your caulk dry, then wrap a few strips of duct tape around the double cap for an extra tight seal. (Alternatively to all this rabble, you can buy one of these suckers.) Screw your completed cap contraption onto one of the bottles.
Fill the other bottle about 3/4 of the way full with water. Add your food coloring (any color will work, but lighter colors seem to “show up” better in this experiment), as well as your plastic confetti. Then, connect the empty bottle to the filled bottle via the double cap thing.
Now, hold your double bottle by the neck (over the duct tape) with one hand, and place your other hand on the bottom of the filled bottle. Swirl the whole thing around in a circle, as vigorously as is reasonable. Then, flip it so the filled bottle is on top and continue to swirl a few more times. Set the bottles carefully on your desk and continue hold onto the top bottle to prevent it from tipping over.
Give Me Vortex or Give Me Death
If you did it right, the water will form its own tornado-esque spinning vortex as it drains from the upper bottle into the lower. The confetti, of course, represents debris caught up in the whirling dervish of death and destruction. Your students can now get a look at the structure of a tornado without risking life and limb.