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Re: transfer of momentum



If I understand John correctly -

He is trying to DOWNplay the equation that most of us rattle off as N2, F=ma.

A MUCH better representation of Force is Newton's own version

F = delta p/delta t

Even for those intro students who are being introduced to SR (or GR),
it is VERY good pedagogy to use the momentum formalism in favor of
the acceleration approach.

Most of us realize how much trouble acceleration causes for our students.

Example - a ball at the top of it's trajectory. What is the
force/acceleration of the ball AT THAT INSTANT!!!

If you think that most of your student 'get this' you are sadly mistaken.

Drawing a momentum vs time graph (or more commonly,velocity vs time)

Gives them a visual picture that answer the difficulty for some/many students.


Acceleration is a VERY difficulty concept.

Momentum is a MUCH simpler and basic concept.

USE it ! ! ! !

OK, ya'll, at 9:56 AM -0500 11/19/03, Bob Sciamanda wrote:
I respect your free choice to use this conceptual model of F=ma in
component form. As with all conceptual models, this is a matter of
taste and free choice; the testable physics lies in the quantitative
relations connecting measurables.

--
Chuck Britton Education is what is left when
britton@ncssm.edu you have forgotten everything
North Carolina School of Science & Math you learned in school.
(919) 416-2762 Albert Einstein, 1936