This week I had to do an experiment to determine which materials would serve as a better insulator. The materials I chose to test were aluminum foil, a piece of sealing plastic wrap, a cotton wash cloth, and a piece of newspaper. To properly complete the experiment, the mugs and the amount of water had to remain constant. I used four of the same types of mugs with 1/2 cup of hot tap water in each cup. My hypothesis was that the plastic wrap would work best. I based my guess on the fact most of our drink covers are plastic and the inside of most coolers are plastic.
The initial temperature of the water was 100 degrees Fahrenheit. After 30 minutes, the temperatures were as follows: newspaper- 92 degrees Fahrenheit, aluminum foil- 94 degrees Fahrenheit, cling wrap- 95 degrees Fahrenheit, and the cotton wash cloth- 93 degrees Fahrenheit. According to these numbers, my hypothesis was correct. But looking at results from some of my colleagues, I'm starting to question my results. From what I've seen the plastic wrap has been coming in last place with some of my fellow classmates. There are couple of factors that may cause the differences. (1) The plastic wrap I used was a cling wrap. It's not like normal plastic wrap. (2) Maybe the wash clothes were different. Maybe mine was a little thinner. (3) There could also have been a human error in reading the thermometers.
Despite the differences, this was still a good experiment that I will use for my students. I may change it up a little bit. Instead of testing which materials make the best insulators for lids, I will probably have them investigate what type of cup will keep a hot beverage warm the longest. They could have several different types of cups (Styrofoam, glass, ceramic, plastic, etc...). Instead of using water, I may let them use hot chocolate. I think they'll appreciate that because it'll be cold by the time we cover heat transfer here in Georgia.
I too used cling wrap instead of plastic wrap. My other coverings included a double-layered cotton dishtowel, a wool sock, and aluminum foil. The dishtowel and wool sock fared the best, while the foil and cling wrap were the poorest. The range of temperature change I experienced was a mere 2.5 degrees Celsius, which I noticed your range too was quite small.
ReplyDeleteOne problem I faced was the ability to pour water into each cup and cover them efficiently. This aspect could be a factor in my results.
Which product did you measure first? How much time elapsed before you measured your last cup? This could have played a role, too.
ReplyDeleteI love the hot chocolate idea. I also think digital term.s would be great.
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