All of this was done with a standing fan set horizontally on a table.
During an experiment, I had to tape a piece of rubber band to one of the standing fan's blade and measured the period of the fan. Taped to the free end of the rubber band is a small metal mass, in the shape of a doughnut. The combined mass of the rubber band and the mass is 1.95 g. At this point, the fan was spinning slow enough that I could approximately count its rotation, just like if I was counting music. I approximated 31 rotations over 5 seconds, which is about 6.2 Hz. Another periodic measurement, using camera, is approximately 187fps over 3.29 seconds, though I'm not sure how to get frequency/period from this.
But when I took the rubber band off, the period/frequency of the fan increased so drastically (that is to say back to its normal period) that I could no longer hear its distinct rotation and count anything. My question is: how did taping a small rubber band with a mass of 2 g affected the period of so drastically?
I have some more data (but not sure which is useful/junk) if any more is needed to calculate anything.