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nincompoop
 one year ago
why is warm air less denser than cool air?
mathematical derivation
nincompoop
 one year ago
why is warm air less denser than cool air? mathematical derivation

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0because the molecules in warm air move faster than cool air, creating more space for every molecule... i think... is that what you need?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.0moving faster does not mean more space

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.2you could play around with pV = nRT

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.0correct you can use pV=nRT and also use kinetic energy from those moving particles

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.2so \(V \propto T\)

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.2so if the air is in a confied space it retains its density but pressure increases in atmosphere air can move  pressure makes it move, so volume etc etc

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.2and then gravity makes it move!!! wind!

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.0fun stuff because we have high and low pressures in the atmosphere as well

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0well you can sub n=m/M

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[PV=\frac{ mRT }{ M }\] \[P=\frac{ mRT }{ VM }\] \[P=\frac{ \rho*RT }{ M }\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Assuming it is a ideal gas you can use the ideal gas equation and the definition of molar mass in the following way. First consider the ideal gas equation \[pV=RnT\] And substitute in molar amount from the definition of molar mass \[n=\frac{ m }{ M }\] This gives you \[pV=\frac{ RmT }{ M }\] Now you can isolate \[m/V\] which is the density \[\rho =\frac{ m }{ V }=\frac{ pM }{ TR }\] As you can see the density is inversely proportional to the temperature. Hopes this answers your question :)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0trying to expand on this..hmm

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0well we can group M/R since they are simply constants, call it A

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[\rho=\frac{ P }{ AT }\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so density is inversely proportional to temperature i reckon

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so at high Temp, density is low relative to low temp (analogous of cold and hot air)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0plus, when people usually say that hot air rises, it is actually false. it depends on the system parameters. Using the nomenclature that hot air pushes up on the cold air would be better

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0and since it pushed up on the cold air, it causes the cold air to be pushed downwards

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.0the differential density investigate both in air and in ocean to see how temperature and density interplay.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0can we assume all pressure is hydrostatic?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.0will that explain welling effect?

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.2i've just googled welling. never heard of it before. now that is interesting...

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.2is that part of life on earth? stuff dredged up by wind and the coriolis force, add a dash of sunshine, keep repeating, and 3 billions years later,... the iPad!!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0hmm, my thermodynamic knowledge may have to come into this...hmm

baewolfstar
 one year ago
Best ResponseYou've already chosen the best response.0Welp I feel stupid

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0that feeling when you get these papers for free at uni. such a gd feeling

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0nup, im done thinking

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0my brain will collapse

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0its an interesting one. we just take this for granted way too easily!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i'm not sure if this help but doesn't hurt looking https://en.wikipedia.org/wiki/Barometric_formula#Density_equations

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i can only think that differential density only comes about with changes in altitude...thats why i was thinking hydrostatic pressure

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.0the rule of thumb on less dense being on top much like oil and water also apply with cool air and warm air when talking about air or air pockets and the atmosphere

baewolfstar
 one year ago
Best ResponseYou've already chosen the best response.0Yup still feel stupid

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.0thank you, guys I wish I can medal you all

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i'd be interested if you could extend my knowledge on this and how we can model it! would be interesting.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0haha i can't believe you can distribute owl bucks. thats hectic
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