Center of Mass Lesson - Balancing Bird

thingiverse

Project #5 - Balancing Bird: Exploring Center of Mass In this project, students will delve into the concept of center of mass/gravity, exploring why a 3D printed balancing bird can spin on its beak without falling off its axis of rotation. A sample 3D STL file is included, borrowed from user mled90. This file is available on Thingiverse at https://www.thingiverse.com/thing:1179531. Print Settings: Printer: Flashforge 3D Creator Pro Resolution: .27 Infill: 15% Notes: A 15% infill should be sufficient for the bird print, but it can be increased if necessary. Post-Printing: Finished prints by user mled90 showcase the original Spinning Balancing Bird STL file. A sample video demonstrates a spinning bird balance (this is not a 3D printed model). Finished 3D Print Designing the Balancing Bird The balancing bird's design can vary, as long as its center of mass remains at the beak, allowing it to balance. The included sample STL from user Mled90 serves as a good example. Standards: NGSS Overview and Background Students in a physics/physical science setting will explore the concept of center of mass/gravity using printed spinning balancing birds. This lesson is a precursor to learning objectives covering center of mass/gravity. Objectives: * Students will develop a fundamental understanding of the concept of center of mass using spinning balancing birds. Audiences: Grades (7-12) Ages (12-18) Skill Levels (all) Skills Learned (Standards): MS-PS2-2. Plan an investigation to provide evidence that the change in an object’s motion depends on the sum of the forces on the object and the mass of the object. Lesson Plan and Activity: Step 1: Explain the activity to students. Step 2: Divide students into groups of 2. Step 3: Distribute balancing birds randomly among all groups. Step 4: Allow students to experiment, finding out where the center of mass is/what position will allow the bird to spin without falling off a point of contact (e.g., a finger). Step 5: Students will test their particular 3D printed balancing bird, determining whether it can spin without falling off its axis of rotation. Step 6: Discuss the concept of center of gravity with students, weighing in on evidence from the spinning bird experiment. Skills Learned: MS-PS2-2 Duration of Lesson: 1 hour to complete exploratory session and discussion Preparation: Requirements: The 3D printed birds should be printed before the lesson. An equal amount of each bird should be printed to distribute evenly across student groups. Small items can also be used to balance the bird, such as bottles or markers. Lab area References: http://www.nextgenscience.org/topic-arrangement/msforces-and-interactions Rubric & Assessment: None -> Teacher may evaluate based on participation and validity based on students who can properly explain why their bird does or does not stay balanced as it spins. Handouts & Assets: None -> See video for example of how to set up bird for spinning.