After recording audio, we analyse the sound with a computer program that identifies individual pulses, measures how much energy is in each pulse, and then makes a histogram, that is, a plot of how many pulses were detected at different energies.
Here we crumpled three sheets of Xerox 4024 paper using the cylinder method, and then cut the data up in thirds over time. One can see that all three curves lie near a straight line in the log-log plot, a sign of a power law distribution. It also is clear that other than a handful of very energetic events which occur near the beginning, there isn't any systematic change in the distribution of pulse energies as the sheet is crumpled. This is odd because the sheet starts out completely flat and ends up profoundly crumpled.
Here we crumpled a number of sheets of medium drawing paper, which is thicker than the Xerox 4024 paper. This time we crumpled different size sheets of paper, but we don't see any systematic change as we do so. (Other than the fact that the total number of events is proportional to the area of the sheet) This is another sign that the process is insensitive to size.
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