Tuesday, July 12, 2011

Things You May Never Have Thought About

How many legs do you have on your stool, and why?  For this discussion it is taken for granted that in all cases outside factors remain equal.  If a 150 pound man had a one legged stool with a bottom area of one square inch then the resultant pressure on the floor while the man sat on it, would be 150 pounds per square inch (PSI).  If this same man obtained a two-legged stool with each leg having a one square inch floor surface it would cut the floor pressure in half, or to 75 PSI.  Going one step further if our 150 pound man went to a three-legged stool the pressure would drop to 50 PSI.
Obviously the more legs on the stool the lesser amount of floor pressure there would be at the point where the legs made contact.  Hold on, not so fast, it ain’t necessarily so.  When you go to a fourth leg it becomes theoretically impossible to make all four legs hit the floor with identical pressures, as can be done with the three former types.  Therefore it becomes impossible to lower the floor pressure to 37.5 PSI.  Theory states that the four legged stool will sit on two opposed legs equally, but will rock back and forth on the other two, effectively placing all of the weight and consequent pressure on two legs much of the time, placing a higher pressure on the floor than in the case of the three legged stool.
Who cares?  Anyone with floors in their home wishing to keep them from excessive wear due to kitchen stools.  Vinyl flooring is especially susceptible to this form of torture.

Do you want to think further along this line?  Okay, how about this one.  Our 150 pound man has a wife who weighs exactly 100 pounds.  Lots of the time she wanders aimlessly in the kitchen with slippers on, barefoot, or wearing some sort of sensible shoes.  In the process of walking her weight is constantly shifting from one foot to the other, but much of the time only on one foot at a time.  Thus her 100 pounds can be divided by the square inches of shoe surface dwindling the floor pressure to a minimal number.
However, from time to time she dons spike heels while preparing to go out for an evening of dining and dancing with her husband.  As she walks through the kitchen, on her way to the attached garage, that 100 pounds of weight applying pressure to a ¼” square area, exerts 1600 PSI on the floor.  Spike heels are death to a vinyl floor, and the husband’s foot also, if he mentions her weight appears to be above that 100 pounds.

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