Bar Conversion: Volume & Temperature Units

AI Thread Summary
The discussion focuses on the conversion of bar to other units, specifically volume and temperature. One bar is defined as 100 kilopascals, which translates to 100,000 pascals or approximately 10,197.162 kilograms-force per square meter. There is some confusion regarding the use of kg/cm² as an equivalent unit for bar, with participants clarifying that while it is commonly used, it is not scientifically accurate. The gravitational constant, g, is accepted as 9.80665 m/s², and there is no official rounding to 10 m/s². The conversation highlights the differences between common usage and scientific definitions of pressure units.
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What the conversion for bar so that I can use it to work out volume and temprature? Whats the units?
 
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Bit higher than I remember, but thanks!
 


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

- Warren
 
Not to be a pain in the ass, 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
 
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.
 
So what is it in hpdpcf's (horsepower-decades per cubic furlong)?

Njorl
 
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
 
You think you're better than me, punk?








- Warren
 
  • #10
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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