Saturday, May 28, 2011

Heat and Temperature Guided Inquiry

      In this guided inquiry I used things that I had around my house to try to find the best insulator to keep hot water in mugs warmest the longest.  I decided to use foil, paper towel, plastic wrap, and newspaper as my insulators.  I then gathered my materials.  I used hot water from the tap, scotch tape, four identical ceramic mugs, the thermometer from my Walden science kit, a measuring cup, and the four insulators I chose to test.  I measured one cup of hot water and poured it in each of the ceramic mugs.  I measured the temperature of the water in each of the mugs and recorded it on my data chart.  I then covered each cup with one of the insulating materials and taped it to keep it in place.  I expected that the foil would make the best insulator and keep the water the warmest.  I thought that the foil would let the least amount of heat escape.  After thirty minutes, I removed the covers from the mugs one at a time and used the thermometer to measure the temperature of the water in each mug.  I recorded my data on my chart. 


Water Temperature in Degrees Celsius
Insulator
Original Hot Water Temperature
Temperature of Water after Thirty Minutes

Foil
Above 50
38
Paper Towel
Above 50
36
Plastic Wrap
Above 50
37
Newspaper
Above 50
36
 
            I hypothesized that the foil would make the best insulator and that is what I observed during this guided inquiry.  However, my results were much closer than I expected.  I thought that the paper towel and the newspaper would allow more heat to escape.  I did not expect for the temperatures of the water in each of the mugs to be within a few degrees of one another.  This inquiry taught my more about conduction, “the transfer of energy from molecule to molecule” (Tillery, Enger, & Ross, 2008, p. 86).  I observed that there was condensation on the top of the foil and the plastic wrap when I removed them from the mugs, and the paper towel and the newspaper was a little moist on the top, which reinforces this idea. 
            I had a couple of challenges in completing this guided inquiry.  I did not have any rubber bands to complete this experiment so I used scotch tape instead.  I wonder if the rubber band would have made a better seal with each of the materials to the mug and allowed less heat transfer to occur.  Also, I was not able to get an accurate temperature measurement of the hot water from the tap when I first put it in the mugs because the thermometer in my science kit only went to fifty degrees Celsius.  I wanted to record the original temperature of the water so that I could make sure that all of the cups started out with hot water that was the same temperature.  I know each mug had one cup of water that was above fifty degrees Celsius, but I do not know for sure that the water was all the exact same temperature to begin with.  If I were going to do this experiment again I would use a different thermometer that is able to measure higher temperatures.
            I enjoyed learning about heat and temperature this week.  I believe my second grade students would enjoy completing a guided inquiry experiment like this as well.  I would probably use food with my students to make the experiment more engaging and have them hypothesize which insulator would keep the food inside the container the warmest the longest.  I think that my students would be very interested in finding out the results especially if I used one of their favorite foods, macaroni and cheese. 

Saturday, May 14, 2011

Momentum of Marbles Guided Inquiry

            The question I choose to investigate for my guided inquiry was:  How do different surfaces affect the momentum of marbles?  First, I thought about all the different surfaces around my house that I could use.  The surfaces I used were:  carpet, tile, concrete, asphalt, and wood.  I decided that I would build an inclined plane using card board and roll the marble down the ramp on each of the different surfaces from the same height.  The height I used for my inclined plane was ten centimeters.  I learned that the marble rolled the shortest distance on the carpet and the furthest on the wooden surface.  I discovered that smoother surfaces allow the marble to roll further because there is less friction and the momentum speeds up the marble and makes it roll further.  My results were what I expected because I knew that friction is a force.  It slowed the momentum down of the marble and eventually caused it to rest.  When the surface is smoother there is less friction so the marble is able to gain more momentum and travel further.  When the surface is rougher there is more friction so the marble had less momentum and the marble will not travel as far.
            I experienced some challenges in completing this guided inquiry.  I had a difficult time finding level surfaces to use around my home.  Many of the surfaces had a slight slope.  Outside my house, there was a slight slope to the concrete and the asphalt surfaces I used.  I tried to use the flattest areas that I could, but I also know that my results are not exactly accurate because of this.  If I were to do this experiment over again, I would make the height of my inclined plane a little shorter.  I think it might have been better to make the height of my inclined plane five centimeters tall instead of ten so that the marble would not have picked up as much momentum on some of the surfaces.  It would be interesting to see the difference in how far the marble rolled on each surface after adjusting the height of the ramp.
            Engaging my students in an experience like this would benefit my students by giving them the freedom to explore a question that I gave them in their own way.  Many times in science, students are not allowed to use their own creativity and ideas to find answers to their questions.  I believe my students could learn a lot about their physical world by investigating questions through guided inquiry.  This is a great opportunity for students to work with others to solve problems and learn from their mistakes.  It would also give me a better understanding of what my students know about the science concept.  I would probably have my students use toy cars on the inclined plane instead of marbles.  I believe that they would be excited to use the toy cars and this would make the experience more relevant to their lives.  I would want my students to learn that smoother surfaces have less friction and that objects can gain more momentum on smoother surfaces and travel further.  I believe that setting up a guided inquiry experience similar to this would allow my students to learn and achieve this goal.