Temperature, kinetic energy !?!

[Guest EAS1601]

Hey,

 

I had a question that i cannot for the life of me figure out, and this is how it goes,

"1. Find the amount of kinetic energy (joules) of the earth's Atmosphere"

 

So i know that temprature is the measure of the kinetic energy that molecules are giving off at a certain time, or something to that extent

 

But I cannot figure out how to convert lets say an average sunny day temprature into joules, if anyone knows how i can do that or if my whole train of thought is off, please tell me

 

Here are 2 other questions that go along with it,

 

2. Find the kinetic energy of a moderate hurricane

3. Find the latent heat released by 5cm of rain over the state of Georgia

 

Any sort of answer that would help me move along on these questions would be appreciated

 

Thanks a lot

[Crash]

1) find the vapour pressure of the atomsphere and work from there.

-What do you mean sunny day temp? from what im guessing the questions asking find out the realtionship between temp and energy? work with specific heat capacitys ot things(very approx.) and go from there,

2)??????? how can you state the mass of a hurricane, i would use rotational kinectic formula, with guess's at the hurricanes unknowns.

3)???????? woulndt have a clue of what gerogias average temp is, what season?

[Dave]

If that's the question, it's a badly worded one. For one, the density and hence mass of the atmosphere is definately not constant.

[greg1917]

If its any help, the equation linking the two is as follows:

 

E = kT

 

E being energy in joules

k being boltzman's constant

T being temperature (rememebr to convert into Kelvin)

[swansont]

If its any help' date=' the equation linking the two is as follows:

 

E = kT

 

E being energy in joules

k being boltzman's constant

T being temperature (rememebr to convert into Kelvin)[/quote']

 

There's a factor of 1/2 for each degree of freedom.

[Guest EAS1601]

Alright I think i figured out questins 2 and 3, but i am still unsure of question one

 

I think i am going to just needed a temperature to energy (easiest way possible)... But i am not so sure about the equation that you gave me, E =kT

 

I looked around on the internet and the closest i came to that equation was: E=(2/3)*k*T, maybe this includes the factor of 1/2 for each degree of freedom.

 

Another thing, looking at this equation, I am unsure whether the units would work themselves out eventually, or do you guys suggest that I should just have blind faith that the units work out?

 

Thanks for the help,

[swansont]

I think i am going to just needed a temperature to energy (easiest way possible)... But i am not so sure about the equation that you gave me' date=' E =kT

 

I looked around on the internet and the closest i came to that equation was: E=(2/3)*k*T, maybe this includes the factor of 1/2 for each degree of freedom.

[/quote']

 

Check again - that should be (3/2)kT

[Guest EAS1601B]

I am also working on the same EAS problems and i can't figure out the atmosphere question. Are you trying to take the average temp of the atmosphere and multiplied by the mass of the atmosphere? Do you think that 3/2kT equation will be valid? Also, if you want to compare any other answers let me know

[Guest EAS1601]

Yea i am sorry you are right it is (3/2), typo

 

Well 1601B , the only thing that I have for that problem is that equation "E=(3/2)kT", and I dont see why it wont be valid. Unless he gave us something, which i am sure he did not. And I certainly dont know how to find the mass of the atmosphere, because like someone already said its not constant.

 

If you find something new about it post it up, other than that I think I got most of the questions figured out, tell me if you are stuck on one or the other.

[Guest eas1601c]

Haha, I'm glad I'm not the only EAS student who found this thread.

 

For the other people who replied regarding the KE of the earth's atmosphere, THANK YOU. I know I totally wouldn't have found that if not for this thread.

 

For the hurricane one, how did you guys get that? I found something here:

http://www.aoml.noaa.gov/hrd/tcfaq/D7.html - but I've been looking for info on the latent heat of condensation, since it leaves out that step, and can't find anything that fills in the gap (I've found some stuff, but it's too cryptic or doesn't fit into the calculations properly)...so right now I'm just writing down what's there and providing the URL, but...I'm wondering if that'd be considered "cheating" or something, though I'm citing my source.

[Guest EAS1601B]

KE of Hurricane=1.5E12 Watts i found that online somewhere. You can easily convert from there. Anyone have any luck for KE of Atmosphere.