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Author Topic: Slug the unit of mass  (Read 9253 times)

Offline erickejah

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Slug the unit of mass
« on: 24/03/2009 21:27:10 »
What do you know about the history of this unit? and if you know about it have you used it for something other than school?


 

lyner

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Slug the unit of mass
« Reply #1 on: 24/03/2009 23:50:33 »
The Slug and the Poundal  are both included in the FPS system because weight (force) and mass are different and because the Pound is / was a quantity, so ingrained in our system  and it was used both as a force and as a mass at the same time. Clearly this is disastrous for serious Science and Engineering.
So a Slug is the mass which, when a pound force acts on it, produces an acceleration of 1fs^-1
And the Poundal is the force which produces an acceleration of 1fs^-1 on a pound mass.

A total bloody mess and full of pitfalls and one would have to say "pound mass" or "pound force" to make oneself totally clear. SI uses entirely different words for Force and Mass so there should be fewer problems - except that people still say they "weigh" 90kg!!!
 

Offline erickejah

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Slug the unit of mass
« Reply #2 on: 25/03/2009 02:04:37 »
"weigh" 90kg!!!
It is funny, because I was one of those few moths ago,  ;D ;D
but now when I say it, it sounds more dramatic ;D ;D
jk
tx Sophiecentaur,

do you why they called it like that?
 

lyner

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Slug the unit of mass
« Reply #3 on: 25/03/2009 09:38:46 »
no eye dear! ;)
 

Offline Chemistry4me

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Slug the unit of mass
« Reply #4 on: 25/03/2009 10:17:21 »
Just one eye dear:
It probably comes from the use of the word ‘slug’ for a lump of crude metal.
 

Offline DoctorBeaver

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Slug the unit of mass
« Reply #5 on: 25/03/2009 10:33:25 »
Slug can also mean a tot of liquour and whoever dreamed those measurements up must have been drunk
 

Offline LeeE

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Slug the unit of mass
« Reply #6 on: 25/03/2009 15:11:22 »
The 'slug' unit is used a lot in aerodynamics.
 

Offline erickejah

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Slug the unit of mass
« Reply #7 on: 25/03/2009 15:33:25 »
tx everyone.  :)
 

lyner

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Slug the unit of mass
« Reply #8 on: 25/03/2009 23:12:27 »
The 'slug' unit is used a lot in aerodynamics.
Only by those on the other side of the pond, I think.
 

Offline LeeE

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Slug the unit of mass
« Reply #9 on: 26/03/2009 16:56:12 »
The 'slug' unit is used a lot in aerodynamics.
Only by those on the other side of the pond, I think.

Hmmm... the old Eastern Block were probably the greatest users of metric systems in aerodynamics, followed by the European countries, excluding the UK.  In terms of the proportion of work done in aerodynamics, I think the majority, mainly in the U.S, and incorporating the little that the U.K. still does, probably still uses 'slugs'.
 

lyner

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Slug the unit of mass
« Reply #10 on: 27/03/2009 19:24:52 »
I often wonder what it is that prevents the US from moving to SI units. The Mars landing disaster alone would have made it worthwhile.
 

Offline LeeE

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Slug the unit of mass
« Reply #11 on: 28/03/2009 22:40:14 »
I often wonder what it is that prevents the US from moving to SI units. The Mars landing disaster alone would have made it worthwhile.

Yeah, to me, SI is a no-brainer.
 

lyner

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Slug the unit of mass
« Reply #12 on: 29/03/2009 13:07:16 »
It's probably the same reason that they stick to baseball.
Fight . . . . fight!
 

Offline syhprum

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Slug the unit of mass
« Reply #13 on: 29/03/2009 14:52:22 »
I think The UK is a world beater with the strange mixture of units we employ, we weigh babies in pounds and ounces,people in stones and pounds, drink milk and beer in pints, record vehicle fuel 'consumption' in miles per gallon although we buy fuel in liters. When I buy groceries I get special English short measure a kilo pack is 900 grams!
The most unbelievable thing about star trek movies is not warp speed or matter transporters but that they use metric measures.
 

lyner

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Slug the unit of mass
« Reply #14 on: 29/03/2009 17:19:12 »
You have a point with the general public but all Science and Engineering is consistent with SI. I only tend to drink pints in pubs or with some 'posh' bottled beer at home. My only real sin is using mpg.

The startrek units go with Picard's exotic European name, I guess. Did James T Kirk ever commit to any measurements apart from Warp?
Put on your Spock ears and impress us with Trekky knowledge.
 

Offline Bored chemist

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Slug the unit of mass
« Reply #15 on: 29/03/2009 17:33:25 »
You have a point with the general public but all Science and Engineering is consistent with SI. I only tend to drink pints in pubs or with some 'posh' bottled beer at home. My only real sin is using mpg.

Do you state your age in gigaseconds if someone asks?
I think most people are much happier with days minutes etc.
BTW, weren't many of the star trek characters meant to be Europeans/ Chinese/ whatever? That would explain the metric units.

And don't gorget, they could still crash the next Mars lander by mixing up Kgf and N.
 

lyner

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Slug the unit of mass
« Reply #16 on: 29/03/2009 19:26:31 »
Kgf is not SI. Are you saying they're dumb?
 

Offline Bored chemist

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Slug the unit of mass
« Reply #17 on: 29/03/2009 22:00:27 »
I don't think anything I could say would matter given their performance.
 

lyner

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Slug the unit of mass
« Reply #18 on: 29/03/2009 23:10:57 »
You are so harsh, BC.
« Last Edit: 29/03/2009 23:13:03 by sophiecentaur »
 

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Slug the unit of mass
« Reply #18 on: 29/03/2009 23:10:57 »

 

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