I appreciate there are many factors that could affect this; vacuum cleaner power, the shape of whatever dust/dirt is being sucked up, the design of the hose walls, to name just a few. I’m looking for a ballpark “top speed”. Any ideas?
Because dust is very small, it should travel at very nearly the same speed as the air.
Your machine should be rated in air watts, and also in pressure. You can roughly derive speed from those two and the cross-sectional area of your hose.
I wonder if the speed of dust in a vacuum is independent of the motion of the janitor.
A rough ballpark figure is probably somewhere around 25 to 50 feet per second.
This little fella could tell ya. Video safe for work (unless you work for PETA). Watch the volume though.