The Heat Is On

In this week's investigation, we were asked to test insulators out to see which item held heat the best in a mug with hot water. Like in week's past, the instructions were fairly vague. The person doing the experiment was able to choose the items they wanted to use as the insulators. The first item of business a person may want to do prior to conducting this lab is to know what the term insulator means: "any material used to slow heat transfer" (www.ase.org, 2010).

The items I selected were a thin piece of cardboard, plastic wrap, a piece of paper, and a piece of linen. I hypothesized that the cardboard would be the best insulator. I chose this item because it seemed like the material that would allow the least amount of heat to escape. The cloth has fibers that will allow air to escape through and cool, the plastic wrap will allow for condensation of water on top and it will fall back into the mug and cool the other water, and the paper will get soggy from the steam of the hot water and will allow for heat to be released.

Once I selected my materials and made my hypothesis, I gathered four ceramic mugs up and filled them with water a temperature of 100 degrees Fahrenheit. One insulator was then placed over each mug secured with a rubber band. A timer was set for exactly thirty minutes. Once thirty minutes had elapsed, the rubber bands were removed and a final temperature reading of each mug was recorded.

Piece of paper final temp: 82
Cardboard final temp: 80
Plastic wrap final temp: 82
Linen cloth final temp: 86

After recording my data, I was surprised to see that my hypothesis was incorrect. I had predicted the cardboard would keep in the most heat and in fact, it held in the least amount. Perhaps I did something incorrect in my experiment or my prediction was just off. Potholders are made from cloth and insulate with cotton materials to keep the heat from burning one's hands. If i would have pondered that aspect more, I may have began with a a different choice at the beginning.

If I were to do this in my classroom and I wanted to make it more relevant to my students, I would use a soup or try it with clothing. For clothing, see if different colored jackets made a difference to being a better insulator for heat. Students could take the temperature inside the jacket. Even if the same project was used, as long as the students were allowed to bring in materials from their own residence to test, I think they would see the relevance and it would be fun. They would have buy in and each group would have different variables. When groups presented their findings, it would be interesting for the class to make a conclusion on what type of materials were better insulators than others.