Re: Models Computational Physics

[Leigh Palmer <palmer@sfu.ca>]

> I do think there is a lot for students to learn by modeling some aspect of
> physics.  The project I have successfully used is the motion of charged
> particles.  The project is to program (from scratch using True Basic or
> Pascal) an animation that shows the motion of three charged particles (
> constrained to act in 2 dimensions) where the mass, charge, and initial
> position of the particles are adjustable (could also add initial velocity).

That sort of exercise is very valuable for the students who succeed. I
can't imagine a better confidence builder for a student who has had
difficulty competing with others in more conventional ways. The key to
Rick's success, I'm sure, is that he has the students do it all from
scratch, the best CAI I can think of.

Several times over the last twenty years I have been approached by a
high school teacher who is eager to show me the marvelous CAI program
he has written. Almost always this involves projectile motion, and in
most cases it was done on an Apple ][ or a PC Jr. in BASIC. The
teacher proceeds to show me how the student can enter initial speed,
inclination angle, turn air resistance on and off, etc. Looking at
the product I can seldom see anything that would be more helpful to
the student than giving him a bucket of rocks and telling him to go
outside and fling them at various speeds and inclination angles and
see what happens. The value of the exercise in most cases lay in its
awakening of physical intuition and enthusiasm in the teacher! In all
my teaching I try to let on that teaching is a wonderful way of
learning. I strongly urge my students to help one another because the
effort that goes into explaining something is all learning process.
We all know that; there's no reason we shouldn't share it with them.

Rick's three body exercise can be expanded to treat gravity and to
more bodies, and I'll bet that a student who has succeeded in solving
the original problem will go off on his own and work on the extended
problems if given the slightest encouragement and access to machines.

What is the success rate and to what sorts of students do you assign
this exercise, Rick?

Leigh