Heat Transfer

I begin my guided inquiry with a question: Which material do you think would make the best insulator?  I know that a conductor allows heat to travel through it.  Therefore, an insulator is going to reduce the heat from escaping a container (Elvidge, 2012).  With this in mind, I went searching for materials in my house that may be insulators.  Since this is a guided inquiry activity, I know I can design the investigation using materials I choose to answer the teacher question (Banchi & Bell, 2008).  The materials I choose to use are foil, plastic wrap, cardboard, and parchment paper.  

 

 

My hypothesis in the investigation is the foil will keep the most heat in the container.  In order to test the insulator, I will use ceramic mugs.  I line up four ceramic mugs on the counter.  Then, I pour in hot water at equal amounts in each mug.  The water is at 38°C at the start of the experiment.  Quickly, I cover each mug with a different material and set a timer for thirty minutes.  At the end of the thirty minutes, I found that the parchment paper held the most heat in at 35°C.  The weakest insulator turned out to be the cardboard.  I thought this would be true since it may have absorbed some of the water vapor taking heat with it.  At the end of the activity, I continued to think about what I knew about heat and convection to justify my outcome.  Convection is the transfer of heat through liquids and gasses (Tillery, Enger, & Ross, 2008).  The foil and parchment paper had the higher temperatures, so they were insulators to keep the heat from escaping.

 Although the experiment was straight forward, I believe I could make it better.  First of all, I only used one thermometer.  I do not think my results were completely accurate due to this fact.  While I measured the temperature of one mug, another sat losing heat until I could reach it.  Also, the thermometer itself was difficult to use since it did not have measuring lines on it.  I actually needed to measure the temperature, than place it along the paper it was glued to in order to record the degree.  I am sure I lost some valuable data in this process.  Also, I did not have enough rubber bands to wrap each material onto the mug.  I did this for cardboard and parchment paper only.  The benefit of guided inquiry is the learning experience and the making sense of the results.

 This would be a great experiment for my students.  I would begin using a video from Teacher’s Domain (I will include the site in the reference section).  This video demonstrates students experimenting with materials to keep an ice cube cold.  This would launch us into our guided inquiry lab.  Students need to test materials to determine the best insulator.  I would allow students to use four cups of various materials.  For example, I will provide Styrofoam, plastic, ceramic, aluminum, etc.  Students will choose their materials and fill with hot water.  Thermometers will be available to each testing material.  Students will record the beginning temperature along with temperature readings every five minutes for a twenty-minute period.  This activity will require consistent observation and teamwork. 

 

References

Banchi, H., & Bell, R. (2008). The many levels of inquiry. Science and Children, 46(2), 26–29. Retrieved on July 8, 2012 from http://web.ebscohost.com.ezp.waldenulibrary.org/ehost/detail?sid=f218157f-411e-4b18-a5ee-9c8577f37f96%40sessionmgr11&vid=1&hid=21&bdata=JnNpdGU9ZWhvc3QtbGl2ZSZzY29wZT1zaXRl#db=ehh&AN=34697743

Elvidge, S. (2012). Keeping Warm or Cold: Insulation and Conduction. Retrieved on September 23, 2012 from http://www.scienceprojectideas.co.uk/keeping-warm-cold-insulation-conduction.html

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

Teachers' Domain. (2004). Testing Insulators: Ice Cube in a Box. Retrieved on September 23, 2012 from 

http://www.teachersdomain.org/resource/phy03.sci.phys.mfe.zice/

 

Engaging in Guided Inquiry

Science education is a combination of questioning, problem solving, and discovery. Therefore, it is essential that students play an active role in their own learning.  Inquiry will allow students to complete hands-on investigations to master science concepts.  While planning my experiment, I immediately put myself in my student’s shoes.  I developed a hypothesis, materials list, procedure, and examined my results.  I will share my experience.

The question I chose to investigate was “how do different surfaces affect the momentum of marbles?” My hypothesis for the investigation is I believe on all surfaces the light blue marble (21 g) will go further then the dark blue marble (8 g).  Since the light blue marble has more mass, it will move further.  “It takes a longer time to stop something from moving when it has a lot of momentum” (Tillery, Enger, & Ross, 2008). To design this experiment, I need to use three surfaces of various textures to help me understand momentum and its relationship to friction.  I will use a smooth granite counter, carpeted area, and grassy section of my yard.  After brainstorming, I decide to use a ramp to release each marble.  This will give me the best results.  As I record data from the experiment, I will need a tape measure and a stopwatch. 

After I completed my experiment, I evaluated my results.  I realized that the more mass an object has, the longer it takes to stop, and therefore it will go further.  This holds true even on different surfaces.  I found both marbles had very similar results on the smoothest surface, the granite counter.  As the surfaces changed and got rougher, the light blue marble went further.  I do agree with my hypothesis reflecting on the lab.  Different surfaces can have an affect on momentum of a marble depending on its mass. Momentum is closely related with Newton’s laws of motion since it involves both inertia and velocity (Tillery, Enger, & Ross, 2008).  This lab demonstrated Newton’s first and second law while the marbles were in motion until an outside force (friction) acted on it.

I can certainly use this experiment with my students.  I would give them a question to explore along with various materials.  I would like to give them some guidance and review expectations before they start.  I would quickly review background knowledge of Newton’s laws, mass, and friction.  This activity did take some time and in the classroom I am confined to forty minutes.  I could make it more interesting for students to bring in their own materials to test.  I could give them the assignment the day before to begin thinking about materials to use and how to test.  I would like my students to walk away from this activity feeling in control of their learning.  I want them to have a memorable experience while developing a deeper understanding of science.  

References

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