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How to abuse a System of Quantities - the human mole

StuartBruff
23-Emerald II

How to abuse a System of Quantities - the human mole

I was reading a science fiction ebook and an exchange along the lines of,

 

"I'm afraid we may have a mole or two in our midst."

"You mean spies?"

 

caught my eye.  And, I couldn't help it, I thought "A mole of spies ... that sounds like an awful lot of spies. Surely somebody would have noticed before then?".  That's the danger of having, a few minutes previously, read a post by @ValeryOchkov on units and Avogadro's number[1].

 

2021 10 09 A.png

 

So, by the titular abuse of notation, ...

 

2021 10 09 B.png

 

There you have it.  The world population is about 13 femtomoles and, in case you were wondering, the total number of humans estimated to have existed is 166 femtomoles.  And as if I didn't feel insignificant enough before, I certainly do after noting that I'm only 1.6 yoctomoles - thank you very much Mathcad Prime Express 7. 

 

... maybe I've made a typo somewhere and it should be an ego-boosting megamole?

 

By a great effort of will, I stopped my fingers from calculating the energy output from a mole of people and how much land they'd need to produce enough food to exist on (and live in without cooking themselves with their own body heat). [3]

 

... OK, so I didn't quite catch my fingers in time and a molesworth of people produce about 48 yottawatts, and that's a lottawatts[2].

 

Stuart

 

[1] https://community.ptc.com/t5/PTC-Mathcad/Changes-in-the-International-System-of-Units-and-Mathcad/m-p/752461#M197623

[2] Yes, all this just for that.  Shah Guido G strikes again.

[3] (I do not want to be the sanitation engineer responsible for dealing with a mole of people!)

5 REPLIES 5

And all that because you were thinking like a chemist rather than a biologist!  😉

Fred_Kohlhepp_0-1633871237988.png

 


@Fred_Kohlhepp wrote:

And all that because you were thinking like a chemist rather than a biologist!  😉


 

Boy, you sure do you know how to hurt a guy's feelings.  Chemist, indeed.  I'm a physicist by education, so I think in terms of moles of quarks.  I'll settle for metrologist, though.

 

Fred_Kohlhepp_0-1633871237988.png


"Look, mate, you scratch my back and I'll scratch yours."

"... A kindly thought, but I think not, my fine, triffid-faced friend."

 

I'm pretty sure they were fighting something like Condylura cristata in the SciFi book I was reading.

 

Stuart

Never meant to insult.  😉 

Chemistry always baffled me, "This is the rule; and these are the two hundred exceptions . . ."  

And I stand in awe of physicists, ever since I flunked out of the physics program, "So, Fred, what ELSE would you be interested in studying?


@Fred_Kohlhepp wrote:

Chemistry always baffled me, "This is the rule; and these are the two hundred exceptions . . ."  


Oh, I agree.  At school we generally took two levels of qualifications:  'O' (ordinary) Levels at about at 15/16, and 'A' (advanced) Levels (at about age 17/18.

 

My memory has never been very good, and 'O' Level chemistry was, as you say, "3 of this and 4 of that gives you a green sludge and goes by this names, whereas 4 of this and 3 of that goes by this name and is a slightly different colour of gross".  None of it seemed to make sense. Physics, to me, was a lot easier, as all I had to do was memorize a few equations and juggle them around to suit the problems.

 

'A' Level Chemistry was totally different - we went into the "why" of what was going on and, suddenly, everything seemed to become crystal(!) clear.   It helped that we had an excellent chemistry teacher.

 

And I stand in awe of physicists, 


As you should, old chap, as you should.  😉 

 

I'm sure standing in awe of physicists is somewhere in the UN Universal Declaration of Human Obligations.  😎  

 

I cant' say that I've noticed an awful lot of it going on, though ...

 


"So, Fred, what ELSE would you be interested in studying?

So, you chose aerospace engineering???  That sounds remarkably like going from out of the frying pan into the fire.   "I failed the audition for 5th horn, so I guess I'm stuck playing 1st violin".  icon_salut

 

Stuart

@StuartBruff wrote:

 

So, you chose aerospace engineering???  That sounds remarkably like going from out of the frying pan into the fire. 

 

Aerospace engineers (IMHO) are mechanical engineers with fancy diplomas.  I couldn't learn the high level math fast enough (we took both vector calculus and electromagnetic theory at the same time.)  So the physics professors took pity on me and steered me into engineering.  (And the Dean of Engineering tried hard to steer me away from aerospace into mechanical!)  That's why I'm such an advocate of Mathcad; it knows how to do the math, I just have to parse the problem correctly. 

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