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what is the equation that expresses the relation between temperature and density?
- RODA MANZI (age 20 )
For a gas obeying the 'perfect gas law' it is straightforward. Since PV = nRT the fractional increase in density, at constant pressure, is equal to minus the fractional change in temperature, for small changes. For a solid it depends very much on which one you are talking about. They vary considerably from material to material. Rather than go into great detail here I would rather point you to the excellent Wikipedia article on the subject where you will find the coefficients expansion for a variety of materials:http://en.wikipedia.org/wiki/Thermal_expansion#Expansion_in_gases
(published on 10/26/11)
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