The friction coefficient was measured for about 80 runs under different conditions. A table of the conditions and results is shown in Appendix-5. The major conditions are:
The sliding situation under this conditions was recorded and edited into Movie 2 and the results are described in this section. Other results are discussed in the section of the comparison experiment.
Movie 2. The sliding of disk on the flour layer. This movie was edited to contain the view of sliding disk from above, the view from end of the sliding , and the track left in the powder layer.