Hot Stuff!

During week four of SCIE-6661S-1, I was challenged to find the best material that would insulate a mug filled with hot water. I chose four materials to test: plastic cling-wrap, foil, newspaper, and a cotton terry cloth. After choosing the materials, each was placed on top of a mug filled with hot water. The materials were secured with a rubber band over the mugs, and the water temperature was tested after thirty minutes.

I predicted that the cling wrap would be the best insulator after doing some research. The best insulators are “materials such as plastic, wood, and rubber [that] hold tightly to their electrons and do not readily allow for the flow of charge” (Tillery, Enger, & Ross, 2008, p. 130).

To my surprise, after thirty minutes the mug covered with plastic wrap measured forty six degrees Celsius. This was less than the newspaper which had a temperature of forty eight degrees Celsius. Both the terry cloth and foil measured fifty degrees Celsius. A factor that may explain the plastic wrap holding the least amount of heat may be related to the thin structure of the plastic. I realized I relied solely on information from the text for my prediction, and did not apply information I already knew. This was a valuable lesson in trusting my own judgment.

This experiment is one that could easily be applied to a classroom setting. To make this relevant to my students’ lives, I would conduct this experiment using a cold liquid rather than a hot liquid. We live in the dessert, so keeping cool and hydrated in the summer is a commonly addressed safety issue. A way to make this experiment more fun would be to have students take part in a “lemonade challenge”. Students would be required to design and test materials that would keep a cup of lemonade the coolest at lemonade stand. Students would study heat transfer in items such as coolers and insulated cups to prepare for their design.

Reference

Tillery, B. W., Enger, E. D., & Ross, F. C. (2008). Integrated science (4th ed.). New York:

McGraw-Hill.

Exploring the Physical World: Engaging in Guided Inquiry

For the assigned guided inquiry experiment, I chose to test the question: “how do different surfaces affect the momentum of marbles?” To create an experiment that would answer this question, I began considering the concepts related to momentum and varied surfaces. Momentum involves mass and velocity. Including velocity in my experiment meant that I needed to have a marble moving in a consistent direction and speed. To do this, I built a simple ramp out of a board of wood propped on a small box. The question I chose asks how different surfaces affect momentum, so I completed two trials; one on carpet and another on tile flooring. To assure the mass was consistent, I used the same marble during each trial. Researching concepts of momentum previous to creating the lab made the design process more efficient.

During the experiment, the marble traveled the furthest on the tile floor. I expected this outcome, as I predicted the carpet has more friction than the tile. The marble traveled only sixty-three centimeters on the carpet. The tile floor had less friction and allowed the marble to travel three point three meters.

The design of the momentum experiment went well, although a challenge I faced was connecting the science concepts to what was happening in the experiment. Physics is not my strong point in science, so I needed to review the concepts involved. This helped me appreciate how my students feel when they are learning new material. I feel that this experience was important for understanding how my students work through the learning process.

Something I appreciated about this assignment was the ability to choose the question I wanted to test. As a student, choice is important to me. It is good to be reminded that choice is a powerful motivator for my students. In the classroom, a modification I would make to this experiment would be to test different marbles or balls that vary in mass. This would provide more evidence that mass is an important factor in momentum. If I were to teach these concepts to my students, I would want them to understand how momentum works. While using a ramp, it would also open up an opportunity to talk about potential and kinetic energy. The experiment I designed would allow students to experience the science behind motion.