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Q & A: standard temperature for water density

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Most recent answer: 12/01/2014
Q:
I read in the fluid mecahnics book . in the topic of specific volume that "physicist use 4 degree Celsius as standard temperature but engeeniers use 15 degree Celsius as standard " I don't found any reason here that why such a difference
- zain (age 18)
pakistan
A:

It's hard for us to answer for the engineers. They have many standards for different purposes. See .

For the density of water, 4°C plays a special role. It's the temperature at which liquid water at atmospheric pressure has the highest density, or minimum specific volume. At that minimum, small changes in temperature have almost no effect on the volume. That makes that 4°C very convenient for high-accuracy measurements. At other temperatures small changes in the temperature make larger changes in volume than at 4°C, so that accurate density calibrations require more accurate temperature control than at 4°C.

Mike W.

 

 


(published on 12/01/2014)

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