Marble Momentum Inquiry
For this week, I chose the “How do different surfaces affect the momentum of marbles?” inquiry to complete. To begin, I looked up the definition of momentum so that I was measuring the correct variable. Momentum is defined as “the product of the mass (m) of an object and its velocity (v)….The law of conservation of momentum: The total momentum of a group of interacting objects remains the same in the absence of external forces” (Tillery, Enger, & Ross, 2008). Therefore I decided to measure the distance the marbles traveled on different surfaces. Without an outside force, such as friction acting on the marbles, the marbles should travel the same distance since I am applying the same force and the marbles are the same mass.
For the different surfaces, I chose linoleum flooring, sand paper, carpet, and felt. The starting point was the same for each marble. I hypothesized that the marble would travel the farthest on the linoleum because the linoleum will have the least amount of friction. After completing the inquiry, I concluded that the marble traveled the furthest was the marble on linoleum. On average, the marble on the linoleum traveled 4.2 meters further than the marble on the carpet, 3.8 meters further than the marble on the felt, and 1.2 meters further than the marble on sandpaper. Through conducting this inquiry, I was able to observe how different amounts of friction (different surfaces) changed the amount of distance the marble was able to travel. I also observed the difference in velocity in relation to the friction. I was also able to better understand the concept of inertia. The marbles required an outside force to travel and depending on the surface, the same force applied to each marble affected the velocity.
If I were to present this question to my students, I am sure they would choose different variables to measure, such as velocity. The way the question is worded lends itself to be measured in different ways. They would also need to have more background knowledge on momentum and inertia. One positive aspect of this inquiry is that it would be simple to extend. The students could decide to extend their knowledge by changing the mass of the marbles on one given surface or change the force applied to the marble. Students enjoy inquiries that allow them to make choices on how they can alter the inquiry to answer another question. Changing the surfaces the marbles travel on was a great way to get students interested in the concept of momentum and could be extended in a variety of ways.
References
Tillery, B. W., Enger, E. D., & Ross, F. C. (2008). Integrated science (4th ed.). New York: McGraw-Hill.
