- #1
Aladin
- 77
- 0
If we want to prove any equation. How we come to know that when and where we have to put the value of this or that formula or when and where we use this or that formula? e.g. (Derive an equation which shows that the absolute temperature is directly proportional to the average translational kinetic energy of the molecules)
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T = 2/3<1/2mv2>=?
As we know
PV=nRT --------- (1) (why did we use this equation for prove above?)
As we know.
n=N/NA (why we don’t put the P=F/A and volume formula)
Put in above equation (1)
PV= N/NA RT---------(2)
Where R/NA= k (k is Boltzman constant)
Equation 2 becomes
PV=NkT
Or
P=NkT/V------------(3) (why we found “P”)
As we know.
P=2/3*N/NA<1/2mv2>-------------(4) (Why we use this equation we can also use this formula)
Comparing 3 and 4. (why we compared)
NkT/V=2/3*N/NA<1/2mv2>.
We get.
kT=2/3<1/2mv2>
or
T=2/3k<1/2mv2>
T=constant<K.E>
T Directly Proportional to <K.E>
Moreover,there are a lot of examples.
I am a college student of 1st year.
I face much difficulty in all these physics Derivations and I learn them by writing again and again. I have neither deep concepts in them nor our teachers tells us about these actual concepts. When we ask about these question that I asked you, hay told that it is just practice. Is it true?
Please explain my this question. I hope that you will solve my this great difficulty in physics.
I will be thankful to you.
Hamid Mahmood
Pakistan
-------------------------------------------------------------------------------------------------------
T = 2/3<1/2mv2>=?
As we know
PV=nRT --------- (1) (why did we use this equation for prove above?)
As we know.
n=N/NA (why we don’t put the P=F/A and volume formula)
Put in above equation (1)
PV= N/NA RT---------(2)
Where R/NA= k (k is Boltzman constant)
Equation 2 becomes
PV=NkT
Or
P=NkT/V------------(3) (why we found “P”)
As we know.
P=2/3*N/NA<1/2mv2>-------------(4) (Why we use this equation we can also use this formula)
Comparing 3 and 4. (why we compared)
NkT/V=2/3*N/NA<1/2mv2>.
We get.
kT=2/3<1/2mv2>
or
T=2/3k<1/2mv2>
T=constant<K.E>
T Directly Proportional to <K.E>
Moreover,there are a lot of examples.
I am a college student of 1st year.
I face much difficulty in all these physics Derivations and I learn them by writing again and again. I have neither deep concepts in them nor our teachers tells us about these actual concepts. When we ask about these question that I asked you, hay told that it is just practice. Is it true?
Please explain my this question. I hope that you will solve my this great difficulty in physics.
I will be thankful to you.
Hamid Mahmood
Pakistan