Magnets, motion and measurement

[Floor]

Preparations for the next magnet interactions measurement set


                     floor

[Floor]

Latest revisions of  two PDF files.

They help to answer the questions ...

what magnitude of force increments to use
                      and
how many measurements to make

when measuring the work / energy present in magnet interactions.

[norman6538]

WOW Floor. Very impressed and very anxious for the resulting numbers.
Norman

[ayeaye]

Floor,

Please add to your paper, if you measure force with a pulley and weight, there are two forces that can be measured at any point. One corresponds to the minimum weight with which the weight still doesn't go up, and the other to the maximum weight with which the weight still doesn't go down. The real force is the average of these two forces, and the static friction of everything, including the pulley, is the half of the difference between these forces.

This is not my idea, i think it is known already from ancient times. Like whenever one uses some balancing scales that are not perfect, and have some friction.

[Floor]

Floor,

The real force is the average of these two forces, and the static friction of everything, including the pulley, is the half
of the difference between these forces.

Thank you eyeeye, good input.

This is already  my standard practice when doing measurements.  However, when measuring in the higher force area
of the curve I find it makes too minor of a difference to do so.   

1. I move the sliding unit BACKWARD (against the weight) a short distance from where it seems to have reached equilibrium between the weight and the magnetic force and then re-release it.

2. Then I move the sliding unit FORWARD (against the magnetic force) a short distance from where it seems to have reached  equilibrium between the weight and the magnetic force and then re-release it.

Although I find that if makes little or no measurable difference in the higher force range, it typically results in an average which is derived from +- 1 degree to as much as +- 2 degrees in the lower force ranges  ( "lower force range" is  <=  25 grams).

                 best wishes
                      floor