In Newtonian Force Dynamics F(dot)dr concerns ANY force and defines a
numerical quantity which enables a rich calculational tool
(http://sciamanda.com/Sans%20Work.pdf) for analyzing a myriad of situations
(oscillators, Kepler orbits, etc) Here Fdx implies NO ( and doesn't even
know of) transfer of "energy". Centuries later Fdx was defined to represent
the transfer of a proposed conserved "energy" . Here, F is defined as that
which makes this analysis valid - it does not apply blindly to ALL forces in
All situations. Confusion has resulted by conflating these two completely
different uses of the symbolism Fdx under the common name "WORK".
Bob Sciamanda
Physics, Edinboro Univ of PA (Em)
treborsciamanda@gmail.com
www.sciamanda.com
-----Original Message-----
From: Anthony Lapinski
Sent: Monday, September 25, 2017 3:31 PM
To: Phys
Subject: [Phys-L] friction
Kinetic friction does negative work on a sliding book, which makes it stop.
And static friction moves us forward when we walk. But there is no
slipping, so static friction does no work on us. Yet we move forward. How
can this be explained to kids in terms of work and energy?