I like to jokingly call this the experiment that never ends. Baloo caught me on Pinterest, and this pin caught his eye:
He immediately begged me to do it, and it looked so simple that I thought we’d give it a try! He wanted to do purple, and we used toilet paper (because we were out of paper towels)
This is about when I discovered that paper towels work MUCH MUCH better than TP. The TP was so slow that the boys lost interest. But when we tried with paper towels (we had to go buy them) it went much faster. Then we noticed that yellow seemed to move through the paper towel much faster than the blue. This discovery led to the last part of our experiment…
We had a few mishaps along the way. With the blue on the far left I accidentally tore the toilet paper. I replaced it with paper towel, which worked much faster. The purple still has the toilet paper in it, thought you can see how much slower it’s going! At this point the purple had been going for well over an hour, whereas the green had been going for about 15 minutes.
If you’re going to try this experiment, I have a few tips for you.
First, fill the water to the top of the cup. Our cups that were half full took much much longer to produce water in the lower cup. Of course, that led to a fun discussion about gravity, which was an interesting part of our experiment. But if you don’t want to test gravity, fill up those cups!
Second, do NOT use toilet paper!! It is slow slow slow!! And it breaks very easily.
Third, definitely make sure to have something to elevate the first cups on. It just makes the process simpler.
Fourth, if you’re doing this with young ones, heat up the water a bit first. For our hot/cold test I just heated up a mug of water for 1 minute in the microwave. It was warm to the touch, but not enough to burn. And it made a big difference in time!