Exploring Center of Gravity

Solar Mobile
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Learning Goal(s):
  1. Students will observe a discrepant event and write down questions about what they observed.

  2. Students will participate in a variety of activities using a meter stick in order to experience and learn about center of gravity.

  3. Students will find the center of gravity of an irregular shaped paper object by using a plumb line.

  4. Students will apply the concept of Center of Gravity and find the center of their solar aircraft that is to be used on their solar mobile. 

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Estimated Activity Length:
2 hours
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Since the concept Center of Gravity (mass) is a key factor in a mobile, students will participate in some activities to help them experience and understand this principle so it can be applied to their final Solar Mobile design. This lesson starts with a teacher demonstration of the discrepant event of a bird that can balance on its beak. Then students will explore center of mass with a meter stick and balls of clay giving them some hands-on experiences. In addition, students can work with various irregular shapes cut out of file folders and find the center of mass of an irregular shape. They can follow the same process as in Center of Irregular Things and find the initial center of mass for their aircraft. 

Other Material(s) Used:
• A meter stick for each student • A small ball of clay • File folder • 50 cm of string • Small dowel (10 cm) for string • 2 washers (to be tied onto the end of the plump line string) • Hand held hole punch • Cut 20” X 30” foam board in half