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Question: What is more powerful, a sneeze or a tornado?
What an excellent questions this is, since the answer to it is so counter-intuitive! There are not many people who would believe that a sneeze- which is in the range of interest of, say, a ladybug - is more powerful than a tornado, which have been known to life trains off their tracks, throw automobiles over rooftops, and flatten whole towns. But the scientific fact is that some sneezes have been recorded to possess greater wind velocities than some tornadoes! Let's consider . . .
According to the Enhanced Fujita Scale (also know as the "F-Scale") a hierarchically ranked classification scale of tornadic wind velocities and associated wind damage, named after the Japanese physicist TT. Fujita who created it in 1971 - tornadoes can possess wind velocities ranging from a relatively weak 40 mph (EF0) all the way up to velocities exceeding 250 mph or higher (EF5). Whereas an EF0 tornado has the power to blow down small trees, tree branches, and cause some mild roof damage to homes, an EF5 tornado can possess enough power to totally destroy buildings, houses, and displace objects weighing tons! The devastating tornado that struck Joplin, Missouri in May of last year was an EF5 tornado.
So how do sneezes compare to tornados? How would a typical sneeze be ranked - in terms of wind velocities alone - on the enhanced Fujita Scale? To answer this, let's consider a typical human sneeze (other mammals sneeze too). The exit velocity of air emitted from the mouth during a sneeze naturally varies, ranging anywhere from a minor puff of air that travels at maybe 10 mph to a feaful blast soaring in excess of 150 mph. In terms of wind velocity, a sneeze of the latter kind is therefore comparable to an EF2 tornado, which is capable of destroying mobile homes, uprooting large trees, and unroofing houses. That's a lot of power, and one good reason why it's not such a good idea to hold sneezes in! But does that mean that you should grab the cat and run for the basement the next time someone at home is on the verge of a sneeze? No, not really - and that's because the Fujita Scale of tornadic wind velocities is also correlated with the potential damage typically inflicted upon physical structures over surface areas measured in miles. According to the NOAA Storm Prediction Center in Norman, Oklahoma, a study of 34 years of tornado tracks revealed that the median path length of a tornado was 0.3 mile and a width of 0.1 mile - and dozens had paths over a mile in width!
Happily, sneezes can't compete with these figures. A sneeze, although windy, is mostly restricted to a narrow passageway emanating from the nose and mouth, and it loses energy quickly against the surrounding stationary air in the immediate environment. As a result, even the more furious species of human sneezes - those of EF2 variety, say - travel only about 12 feet before, fighting its way through stationary air, it gradually comes to rest. The environmental damage achieved by the sneeze is therefore usually quite unremarkable - unless, of course, you are a ladybug.
So we needn't worry about demolishing your home or school with a sneeze, even though it represents an event of considerable power in the vicinity of the nose. They are our "inner tornadoes," as it were, and deserve our respect.
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