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ERIC Number: EJ1143048
Record Type: Journal
Publication Date: 2017-Jul
Pages: 5
Abstractor: As Provided
ISSN: ISSN-0031-9120
The Bottle Flip Challenge Demystified: Where Is the Centre of Mass?
Carvalho, Paulo Simeão; Rodrigues, Marcelo José
Physics Education, v52 n4 Article 045020 Jul 2017
Bodies can have very weird trajectories when tossed into the air. The amazing motion of a water bottle flip is qualitatively described as related to the position of the centre of mass (CM) with respect to the body's frame of reference. Although this is rather easy to guess from simple observations, it is not so obvious to verify quantitatively with the naked eye. In this work, we use video analysis and a computational model to show that the position of the CM changes in the frame of reference of the bottle, while it describes a parabolic trajectory in the frame of reference of the laboratory. We also show that the behaviour of the CM also explains the weird motion of the bottle. It can be observed graphically and discussed in the classroom with students, as it only needs some critical thinking and practically no math.
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A