Scientific Inquiry

Sunday, January 15, 2012

Scientific Inquiry

I designed an inquiry based experiment around the the question which referred to the effect that large objects have when colliding with smaller objects. I used a small and large marble as part of my experiment. The results of my experiment provided examples of Newtons first and second laws of motion. When carrying out my experiment, I discovered that the large marble hit the small marble and continued to roll a distance of five feet before stopping. This insight was contrary to my predicted results. Originally I hypothesized that the large marble would hit the small marble and stop without traveling any distance. The small marble continued to roll a distance of twenty feet after impact until it collided with the wall of the classroom.
The experiment went well. I learned a lot form the experience particularly when my hypothesis was rejected. I would modify the assignment by repeating the experiment on different surfaces other than carpet. I would then compare the data and draw conclusions form the results.
I would like to use this activity in my classroom. As an extension we would connect to the real-world experiences of skiing and snowboarding. We take a ski trip each winter. We would connect our in -class discussion of mass, velocity, force and acceleration to our winter sports experiences.
One of the most important things I would like my students to learn from this experience is to understand the laws of motion and how to recognize examples of Newton' s laws in our everyday lives.

Heat Transfer - What is the best Insulator?

The insulating materials that I selected were a paper towel, cotton cloth, aluminum foil and plastic wrap.  I chose these materials because they were readily available.  To begin, I cut all materials into eight inch square pieces to ensure that the same length of material overlapped the edge of each mug.  I boiled the water to one hundred seventy-five degrees Fahrenheit so that I would have a constant temperature variable to compare my results to.  I carefully added a cup of hot water to each of the four identical mugs and then covered the mugs with the insulating materials.  Rubber bands were used to secure the insulating materials tightly to the top of each mug. 

After thirty minutes, the water in the paper towel covered mug was 110 degrees.  The water in the cotton cloth and plastic wrap mugs were both 115 degrees.  Finally, the water in the aluminum foil mug measured a temperature of 117 degrees Fahrenheit.   

My hypothesis was not supported by the outcome of my experiment.  I hypothesized that the cotton cloth would be the best insulator due to its thickness and pockets of air contained within its fibers.  The aluminum foil was the most efficient insulator.  After thirty minutes the water temperature in the aluminum foil covered mug was the warmest.   

If I designed a similar experiment for my students, I would make it more fun and engaging by having them design insulating covers for pop cans.  This experiment would have relevance to my students lives because during the summer months it gets hot in our region of the state.  There is nothing like a cold drink on a hot summer day.  Students could design covers using a variety of materials.  Through personal investigation, students would discover which materials are effective insulators.