Brenternet (The World as seen by Brent Moore)

Trying to appeal to the highest common denominator. I can't give you 110% effort, but I will give you 107.4% effort. If you're a spammer and leave me a comment, I will make fun of you. I use twice as many semicolons compared to most other bloggers

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Location: Smyrna, Tennessee, United States

As the title implies, I am Brent K. Moore. I married MariLynn Simons on Sept. 25, 1999. we attend Stewart's Creek Church of Christ. We have five pets, a dachshund, Slinkie, a malamute, Juno, and three rabbits, Ebunny and Ifurry, and now Houdini.

Monday, May 30, 2005

The Vindication of Fahrenheit and 98.6

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What is the average human body temperature? Ask most any scientist, or, well, anybody, and they will tell you 98.6 degrees Fahrenheit.

When I was in middle school, I vaguely remember being taught that when Mr. Fahrenheit devised his scale, he designed 100 degrees on his scale to be the human body temperature. Did he miss?

How many people can recall the formula to convert from Fahrenheit to Celsius?
Tc = (5/9)*(Tf - 32)
Tc = (5/9)*(98.6 - 32) = (5/9)*66.6 = 333/9 = 37

When the human body temperature was first measured, scientists used Mr. Celsius's scale, and it was done at a time before anyone could measure temperature with anything more accurate than to the nearest degree. In other words, they could measure a pot of water to be 24 degrees Celsius, not 24.219 degrees Celsius.

Anyone who took a science lab course in high school or college was exposed to Significant digits (or figures). What was the rule of multiplication and division with Significant digits. When measurements are multiplied or divided, the answer can contain no more significant figures than the least accurate measurement. If you don't believe me, check Purdue's chemistry department website. (I picked this website as it was the first one I found on Google.)

There is our first problem. Converting 37 C to 98.6 F creates significant digits breaking the previous rule. My teacher would subtract 5 points from my grade for that! We should be saying 99 F, shouldn't we?

With what I have said so far, the human body temperature could be anything from 36.50 to 37.4999…. C which calculates to 97.7 to 99.49999 F. So it doesn't quite make it to 100 F, and Mr. Fahrenheit was off by a bit, but theoretically he could have been more accurate than the currently accepted standard of 98.6 F. Think about it: Have you ever heard of someone who had a fever of 99.7?

Next, today's scientific equipment could probably measure temperature to 1/1000th of a degree, I would think. Why don't we? Two reasons I can think of:
1) The human body temperature does fluctuate. "... the normal range for body temperature is 97 to 100 degrees Fahrenheit or 36.1 to 37.8 degrees Celsius"
2) Who wants to go around challenging a scientifically accepted fact? You might as well say the sun sets in the North.

What I say here will never change anyone's mind. A science teacher who goes around saying the human body temperature is 99.5 will happen once an English teacher says I can use passive voice on my term paper.

Just be thankful we don't use Rankine.
(or Reaumur or Delisle for that matter.)


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