Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: Conservation of ME and nonconservative forces



At 02:27 PM 6/28/01 -0500, QUIST, OREN wrote:
The problem is for a freshman level physics class.

Actually, in my freshman level physics class, they roll a ball down a ruler
and measure the speed at the bottom (actually the table). So I guess I
agree.

We can be as accurate and precise
as we want to be. But, we should not be more accurate than has meaning for
a specific case. Students need to see the simplicity and elegance of
physics without getting totally bogged down in unneeded details. Leave
these for the more advanced classes.

While a detailed analysis of these other factors may be for more advanced
classes, I think some kind of analysis is appropriate for the freshman level
class. For example, in my class the students find that the resulting speed
is less than that predicted using Cons of energy with mgh and 0.5mv2. They
are then asked to determine which of many assumptions (including resolution,
precision, rotation, air resistance, slipping, bouncing, etc.) contribute
the greatest to the discrepancy. They have to support their argument with
measurements (not theory).

----------------------------------------------------------
| Robert Cohen Department of Physics |
| East Stroudsburg University |
| rcohen@po-box.esu.edu East Stroudsburg, PA 18301 |
| http://www.esu.edu/~bbq/ (570) 422-3428 |
----------------------------------------------------------