Learn more physics!
does the "3 second rule" actualy work?
will bacteria on the floor get on it more if it is left there longer or does it not mater
would it mater at 5 or more sceonds (everyone has their own variaton on the number of seconds)
Nope, all of these "rules" are rubbish. It does not take any time to
transfer bacteria from one surface to another when they are in contact
(in fact, that's what "contact" means -- electromagnetic forces are
felt between the two objects.) When two objects are in contact, any
fluid on one surface may wet the other, and carry bacteria along.
If these rules were for real, you'd never be able to wipe anything
off the floor with a towel. All the bacteria (which do not have little
stopwatches) and water and other stuff (which also does not have a
stopwatch) would somehow have to wait the allotted time before being
able to get wiped up. If you mop up a spill on the floor with your
pizza, whatever was on the floor will be on your pizza, no matter how
little time it took you to do it.
(republished on 07/17/06)
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