science for tinies: soaking
Jan. 18th, 2014 05:18 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
psocopteraProject: What Soaks Faster?
Materials: yogurt cups, paper towel, water, olive oil, maple syrup, ketchup
Explanatory details: The other day Junie requested more syrup for her waffles. "But you've already poured on tons", Josh pointed out. "But I can't see it," Junie argued. "It soaks in," Josh explained. "But when I put on ketchup I can see it," Junie argued. And thus we formed a hypothesis: syrup soaks in faster than ketchup.
Does syrup soak in faster than ketchup? We measured a tablespoon of water into a (clean, dry) yogurt cup. Then we dried the spoon and measured a tablespoon of oil into another cup. Then we eyeballed a similar amount of syrup and ketchup into the remaining two cups (rather than have to scrape out the spoon). Junie cut a paper towel into four equal strips, and we put one into each cup.
How did it go: Good! We checked our experiment after ten minutes. The water had soaked all the way to the end of the paper towel. The oil had soaked up partway. We decided that we should measure with a ruler how far up the paper towel had been soaked. The water had soaked 6 inches to the top. The oil had soaked up 3 inches. The ketchup had soaked up 2 and a half inches, and the syrup had also soaked up 2 and a half inches. So, the syrup had not soaked any faster than the ketchup!
We decided to do a second experiment. (Where by "we" I mean "me", Junie had wandered off to do some painting by then. But I showed it to her and she looked briefly and we talked about it.) I dipped the end of a straw into each liquid and then dotted it onto a clean paper towel, and then measured how wide it spread out. The water spread out to 1 and a half inches. The oil spread out to one inch. The syrup and the ketchup each spread out to just under half an inch, but we could see something interesting: all of the syrup had soaked in, but the ketchup had a watery part that had soaked in, and a red goopy part that was still sitting in a little peak on top of the paper towel. We concluded that ketchup has a part that soaks in and a part that doesn't soak in.
(Could we separate those parts? I did a quick Google search on centrifuging ketchup and learned that ketchup does not separate under 13000g for 30 min. Then I tried to explain this to Junie and concluded that we needed to do some more science to explain centrifugation, as my explanation with materials I had at hand (involving waving around a shirt someone had left on the table) was somewhat lacking...)
Things we talked about: Well, we didn't really talk about this explicitly, but by measuring with the ruler, we turned our observation of what was happening into numbers.
What Junie got out of it: She thought it was fun to get to play with ketchup and oil and stuff. Also I feel like it was a good demonstration of the idea that you can notice something interesting (the initial question about ketchup vs syrup) and devise an experiment to learn more about it.
Materials: yogurt cups, paper towel, water, olive oil, maple syrup, ketchup
Explanatory details: The other day Junie requested more syrup for her waffles. "But you've already poured on tons", Josh pointed out. "But I can't see it," Junie argued. "It soaks in," Josh explained. "But when I put on ketchup I can see it," Junie argued. And thus we formed a hypothesis: syrup soaks in faster than ketchup.
Does syrup soak in faster than ketchup? We measured a tablespoon of water into a (clean, dry) yogurt cup. Then we dried the spoon and measured a tablespoon of oil into another cup. Then we eyeballed a similar amount of syrup and ketchup into the remaining two cups (rather than have to scrape out the spoon). Junie cut a paper towel into four equal strips, and we put one into each cup.
How did it go: Good! We checked our experiment after ten minutes. The water had soaked all the way to the end of the paper towel. The oil had soaked up partway. We decided that we should measure with a ruler how far up the paper towel had been soaked. The water had soaked 6 inches to the top. The oil had soaked up 3 inches. The ketchup had soaked up 2 and a half inches, and the syrup had also soaked up 2 and a half inches. So, the syrup had not soaked any faster than the ketchup!
We decided to do a second experiment. (Where by "we" I mean "me", Junie had wandered off to do some painting by then. But I showed it to her and she looked briefly and we talked about it.) I dipped the end of a straw into each liquid and then dotted it onto a clean paper towel, and then measured how wide it spread out. The water spread out to 1 and a half inches. The oil spread out to one inch. The syrup and the ketchup each spread out to just under half an inch, but we could see something interesting: all of the syrup had soaked in, but the ketchup had a watery part that had soaked in, and a red goopy part that was still sitting in a little peak on top of the paper towel. We concluded that ketchup has a part that soaks in and a part that doesn't soak in.
(Could we separate those parts? I did a quick Google search on centrifuging ketchup and learned that ketchup does not separate under 13000g for 30 min. Then I tried to explain this to Junie and concluded that we needed to do some more science to explain centrifugation, as my explanation with materials I had at hand (involving waving around a shirt someone had left on the table) was somewhat lacking...)
Things we talked about: Well, we didn't really talk about this explicitly, but by measuring with the ruler, we turned our observation of what was happening into numbers.
What Junie got out of it: She thought it was fun to get to play with ketchup and oil and stuff. Also I feel like it was a good demonstration of the idea that you can notice something interesting (the initial question about ketchup vs syrup) and devise an experiment to learn more about it.
