One dimension - Freefall of a baseball and a piece of paper [video]
Authors
Denardo, Bruce
Subjects
Advisors
Date of Issue
2014-07
Date
Published on Jul 21, 2014
Publisher
Naval Postgraduate School, Monterey, California
Language
en_US
Abstract
Here I hold a horizontal piece of paper and a baseball at the same height from the table. I then ask which will strike the table first, if they are simultaneously released from rest. After receiving their responses, I then crumple the paper into as compact spherical shape as possible, and the baseball and paper are then simultaneously released from rest at the same height. They strike the table at nearly the same time. This demonstration dramatically points out the dependence of air resistance upon geometry. In the next demonstration, the book and a sheet of paper are both held horizontally at the same height and are simultaneously released from rest. A magazine works well as an alternative to a book. I then ask the students which object will have the greater acceleration in each of three different cases. "Drafting," in which an object substantially reduces the air resistance on another object behind it (as employed in bicycle racing), does not fully account for the effect here. This is because the paper can overhang the book by a small amount, but the paper still accelerates the same as the book. There is apparently a suction effect that tends to maintain the paper in contact with the book.
Type
Video
Description
NPS Physics EDU
Series/Report No
Department
Physics
Organization
Naval Postgraduate School (U.S.)
Identifiers
NPS Report Number
Sponsors
Funder
Format
Duration: 4:53 Filesize 53.6 MB
Citation
Distribution Statement
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.