Timeline for How does a virus fall down in static air?
Current License: CC BY-SA 4.0
5 events
| when toggle format | what | by | license | comment | |
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| Dec 20, 2021 at 18:14 | comment | added | Eph | I'm with @jpa on this.. the sedimentation length is talking about particles with a high concentration such that concentration changes by a factor of e for every sedimentation length. So your concentration of virus near the floor should be $e^{\frac{3}{4.2*10^{-7}}} = 10^{194163} $ times the concentration at the ceiling. In practice this would mean that if the air happened to be completely still in a room, eventually the virus would settle such that having a single particle higher than a few centimeter above the ground would be astounding. However, the air isn't still, so not very applicable. | |
| Dec 20, 2021 at 10:24 | comment | added | Vladimir F Героям слава | @Pathfinder Yes, air is a fluid. Both gases and liquids are fluids. | |
| Dec 20, 2021 at 9:50 | comment | added | MatterGauge | What about the force of gravity pulling the virus down? Is that contained in sedimentation length? | |
| Dec 20, 2021 at 6:47 | comment | added | jpa | Hmm, according to wikipedia "At the length l_g above the reference point, the concentration of colloidal particles decreases by a factor of e.". Wouldn't that mean with a sedimentation length of 400 nm, the probability of finding a particle at the roof would be exp(-3m/400nm) = pretty much zero? | |
| Dec 20, 2021 at 3:46 | history | answered | Elmore | CC BY-SA 4.0 |