ALI

Rolling Lab



Students should be having a thorough knowledge in mechanics by now. This would be an end of year project. Students will already know what moment of inertia is and that a sphere rolls down an incline at a faster rate than a solid cylinder which inturn will beat a ring.They also know that the mass and radius of the sphere, solid cylinder and ring doesnt affect the speed. Neglecting air resistance spheres of any size should be reaching the bottom of an incline at the same time and so is the case with solid cylinder and ring. Students will each bring a cylindrical food can of any size.They will be divided into groups of four. Each group has to predict the winner in their group (the fastest can and the slowest can). They should give a reasoning for that based on prior established knowledge. They would then have a competition within each group with the cans. They will have two winners from each group, the fastest and the slowest. Each group has to present their prediction and the actual winners and provide a logical reasoning for why they chose their prediction and why it worked or it did not. The winners from each group will have the competition again and the final winners will be given a token of appreciation.The whole class would share their ideas and misconceptions for the last 5-10 min of the class. The food cans will then be donated to the food bank. The whole learning process is to take the students to a higher cognitive level of predicting and analyzing based on prior knowledge.This activity would make them apply the concept that for a rolling object, if the moment of inertia is greater, then the potential energy at the top of the incline is uitilized more for rotation than translation and hence less speed. They will also think more about how the moment of inertia of different food cans differ based on the the mass distribution around the center of rotation. __Learning Target:__ 1) Students will be able to predict, test and analyze a hypothesis using prior knowledge. //__WA Science EALR 2.3 9-12 INQC Explain:__ Conclusions must be logical, based on evidence, and consistent with prior established knowledge.// //__WA Science EALR 2.7 9-12 INQG Intellectual Honesty:__ Public communication among scientists is an essential aspect of research. Scientists evaluate the validity of one another's investigations, check the reliability of results, and explain inconsistencies in findings.// __Assessment:__ Students will be assessed based on their performance in their group discussions and final group presentation. __Materials Required:__ Inclines with measuring scale, cylindrical food cans, stop watch, handouts,doc-camera __Step by Step Activity:__ (10 min) Students are divided into groups of four for this activity using different colored popsickle sticks. Teacher should explain the activity to students and distribute the handout explaning it. (30 min) Each group has to predict the fastest and slowest food can winner in their group. Each group has to roll the cans down an incline to find the actual winners. (The angle of incline should be less to get more accurate results. The students have to figure that out themselves. They also have to figure out the number of trials taken and other accuracy methods for the activity) Teacher should go around and listen to their predictions and reasoning for that. Teacher should also monitor them while doing the activity and make note of their points. (20 min) Students has to present (in groups of four) their predicted winners, logical reasoning for the choice and why the actual winner was consistent or not consistent with the predicted one. Teacher has to check for the logical reasoning and see if they are mentioning any inaccuracies you have observed while they did the lab and ask questions on what you have observed. (10 min) Now the fastest winners from each group have to present their cans.Students have to predict the fastest among these. The same should be done with the slowest winners. The winners of each group should then have a competition and the fastest and the slowest winner is selected. Each group has to cheer for their group representatives. __Closure (5 min):__ Students are given a question as a closure activity. 1) Which one of these cans would roll down an incline faster ? a) A can of fruit juice b) A can of frozen fruit juice Give your reasoning. Teacher should collect this work. The food cans are then donated to the food bank.
 * Grade Level:** 10-12/AP Physics
 * Time:** 90 min
 * Established Prior Knowledge:**
 * Overview and Rationale:**
 * Learning Targets, WA state Standards and Assessment:**
 * Description:**



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