1 Bar = ?


by BMcN
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BMcN
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#1
Nov17-03, 11:22 AM
P: 11
What the conversion for bar so that I can use it to work out volume and temprature? Whats the units?
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Ambitwistor
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#2
Nov17-03, 11:28 AM
P: 837
1 bar = 100,000 pascals = 100,000 kg/m/s2
BMcN
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#3
Nov17-03, 11:29 AM
P: 11
Bit higher than I remember, but thanks! [:D]

chroot
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#4
Nov17-03, 11:52 AM
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1 Bar = ?


Originally posted by Ambitwistor
1 bar = 100,000 pascals = 100,000 kg/m/s2
Should be kg/m-s2 [:D]

- Warren
Ambitwistor
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#5
Nov17-03, 11:57 AM
P: 837
Either way works.
chroot
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Nov17-03, 12:10 PM
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Not to be a pain in the ***, but I'd normally think

kg/m/s^2 = kg s^2 / m

But I guess it does come down to the conventional order of operations. I guess you win. Gack. I personally hate when people describe accelerations as "meters per second per second" i.e. m/s/s, for the same reason.

- Warren
Chi Meson
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#7
Nov18-03, 01:13 PM
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Interesting note:

In the "common" world, a bar has the unit "kg/cm^2". THis is referring to the weight of one kilogram per square centimeter. THis of course translates to only 98,010 N per square meter, but somewhere along the line, "g" got upgraded to 10 N/kg instead of 9.801 N/kg.
Njorl
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#8
Nov18-03, 01:36 PM
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So what is it in hpdpcf's (horsepower-decades per cubic furlong)?

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chroot
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Nov18-03, 01:41 PM
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Originally posted by Chi Meson
Interesting note:

In the "common" world, a bar has the unit "kg/cm^2". THis is referring to the weight of one kilogram per square centimeter. THis of course translates to only 98,010 N per square meter, but somewhere along the line, "g" got upgraded to 10 N/kg instead of 9.801 N/kg.
Uh.... no.

1 bar is defined to be 100 kilopascals. A pascal is one newton per square meter. One kilogram-force is g newtons. Therefore, one pascal is (1/g) kilogram-force per square meter. Therefore, one bar is 100,000/g kilograms-force per square meter.

g is accepted to be 9.80665 m/s^2, so one bar is 10,197.1621298 kilograms-force per square meter.

I have no idea where you got the idea that someone rounded g to 10 m/s^2, but it never happened.

- Warren
Ambitwistor
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#10
Nov18-03, 02:27 PM
P: 837
So what is it in hpdpcf's (horsepower-decades per cubic furlong)?
1 bar = 3.4595574 hpdpcf's
chroot
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#11
Nov18-03, 02:29 PM
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Originally posted by Ambitwistor
1 bar = 3.4595574 hpdpcf's
I see your Schwartz is as big as mine.

http://www.google.com/search?num=100...=Google+Search

- Warren
Ambitwistor
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#12
Nov18-03, 02:34 PM
P: 837
I used the Unix 'units' program, since I had a shell already open ...

$ units
2084 units, 71 prefixes, 32 nonlinear units

You have: bar
You want: horsepower-decade/furlong^3
        * 3.4595574
        / 0.28905432
chroot
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#13
Nov18-03, 02:37 PM
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You think you're better than me, punk?






[:D]

- Warren
Chi Meson
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#14
Nov19-03, 10:35 AM
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Originally posted by chroot
Uh.... no.

1 bar is defined to be 100 kilopascals. A pascal is one newton per square meter. One kilogram-force is g newtons. Therefore, one pascal is (1/g) kilogram-force per square meter. Therefore, one bar is 100,000/g kilograms-force per square meter.

g is accepted to be 9.80665 m/s^2, so one bar is 10,197.1621298 kilograms-force per square meter.

I have no idea where you got the idea that someone rounded g to 10 m/s^2, but it never happened.

- Warren
That's not what I meant, really. In Europe, the unit of bar and kg/cm^2 is used interchangeably (not by scientists, but by people pumping their bike tires). I remember several times over the years hearing anecdotaly that the bar was based on the "kg/cm^2" but was then redefined to be essentially 10 N/cm^2 (actually 1,000,000 dynes per cm^2)to be scientifically correct.

So g was not the one that was adjusted. It's the bar that was raised.


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