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Doing work on oneself



A passage from a problem in the current edition of a very popular college
physics text:

"A 55.0-kg skateboarder starts out with a speed of 1.80 m/s. He does
+80.0 J of work on himself by pushing with his feet against the ground.
..."

If we really aren't willing to get into the minor subtleties of internal
energy conversions, pseudowork, etc., wouldn't you think we could at least
avoid problem statements that send such horrendously improper messages?

My gripe of the day,

John
-----------------------------------------------------------------
A. John Mallinckrodt http://www.csupomona.edu/~ajm
Professor of Physics mailto:ajm@csupomona.edu
Physics Department voice:909-869-4054
Cal Poly Pomona fax:909-869-5090
Pomona, CA 91768-4031 office:Building 8, Room 223