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Re: Welcome
bocho1986bocho1986 1237418238|%e %b %Y, %H:%M %Z|agohover
in discussion General Forum / Discussion » Welcome

Hello,

I will start to solve several problems on this book starting this coming week. I will like to help by posting the solutions. Can you provide the password so I can post solutions? email me at ude.csu|orravanf#ude.csu|orravanf.

Thanks,

Francisco

Re: Welcome by bocho1986bocho1986, 1237418238|%e %b %Y, %H:%M %Z|agohover
Problem 7
smnhasansmnhasan 1225332404|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 12 / Solutions » Problem 12-7

Can any one please solve it for me?

Problem 7 by smnhasansmnhasan, 1225332404|%e %b %Y, %H:%M %Z|agohover
Solution: Problem1-46
siromasiroma 1222692955|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 1 / Solutions » Solution: Problem1-46
(1)
W(X,Y)=X+Y
Expected value of W:
(2)
\begin{tabular}{ccl} E(W) & \stackrel{\text{by def.}}{=} & \iint{(x+y)f(x,y)dxdy \ & = & \iint{xf(x,y)dxdy} + \iint{yf(x,y)dxdy \ & \stackrel{\text{indep.} }{=} & \iint{xf_1(x)f_2(y)dxdy + \iint{yf_1(x)f_2(y)dxdy\ & = &\int{xf_1(x)dx}\int{f_2(y)dy} + \int{yf_2(y)dy}\int{f_1(x)dx}\ & = &\int{xf_1(x)dx} + \int{yf_2(y)dy}\ & = & E(X)+ E(Y) \end{tabular}
Variance of W:
(3)
\begin{tabular}{ccl} Var(W) & \stackrel{\text{by def.}}{=} & \iint{((x+y)-E(X+Y)})^2}f(x,y)dxdy \ & = & \iint{((x-E(X))+(y-E(Y)))^2f(x,y)dxdy} \ & = & \iint{(x-E(X))^2f(x,y)dxdy + \\ & & 2\iint{(x-E(X))(y-E(Y))}f(x,y)dxdy + \ & & \iint{(y-E(Y))f(x,y)dxdy\ & \stackrel{\text{indep.} }{=} & \int{(x-E(X))^2f_1(x)dx\int{f_2(y)dy} +\ & & 2\int{(x-E(x))f_1(x)dx}\int{(y-E(y))f_2(y)dy}+\\ & & \int{(y-E(Y))^2f_2(y)dy\int{f_1(x)dx}\ & = & Var(X) + Var(Y) \end{tabular}
Solution: Problem1-46 by siromasiroma, 1222692955|%e %b %Y, %H:%M %Z|agohover
Solution: Problem1-57
siromasiroma 1222339519|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 1 / Solutions » Solution: Problem1-57

Geometric progression sum formula derivation:

(1)
S_n=\sum_{n=0}^\infty {q^{n}a_0}=a_0+qa_0+q^2a_0+...+q^na_0
(2)
qS_n=q\sum_{n=0}^\infty {q^na_0}=qa_0+q^2a_0+q^3a_0+...+q^{n+1}a_0
(3)
(q-1)S_n=q^{n+1}a_0-a_0
(4)
S_n=a_0\frac{q^{n+1}-1}{q-1}

If q<1 then

(5)
\lim_{n \to \infty } S_n = a_0\frac{1}{1-q}

In the problem a_0=1 and q=e^{-\alpha} therefore we require that e^{-\alpha} < 1; thus when \alpha>0 we have closed sum

(6)
\lim_{n \to \infty } S_n = \frac{1}{1-e^{-\alpha}}

On the other hand,

(7)
I=\int_{0}^{\infty}{e^{-\alpha n}}dn = -\frac{e^{-\alpha n}}{\alpha} |_0^\infty = -\frac{1}{\alpha}(\lim_{n \to \infty} e^{-\alpha n} - 1)

Because \alpha>0

(8)
I = \frac{1}{\alpha}

To find required \alpha we have

(9)
\frac{1}{\alpha}=\frac{1}{1-e^{-\alpha}}

or

(10)
e^{-\alpha}=1-\alpha

Equation (10) has only one solution(this can be shown comparing derivatives of rhs and lhs functions):

(11)
\alpha=0

To satisfy requirement of \alpha > 0 we give result in limit form:

(12)
I \to S \text{ when } \alpha \to 0^+
Solution: Problem1-57 by siromasiroma, 1222339519|%e %b %Y, %H:%M %Z|agohover
Solution: Problem1-55
siromasiroma 1222308579|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 1 / Solutions » Solution: Problem1-55
Even function
f(x)=f(-x)
(1)
f(-x)=\frac{e^{-x}}{(1 \pm e^{-x})^2}=\frac{e^{-x}}{(1\pm\frac{1}{e^x})^2}=\frac{e^{-x}e^{2x}}{(e^x\pm1)^2}=\frac{e^x}{(1 \pm e^x)^2}=f(x)

QED

Solution: Problem1-55 by siromasiroma, 1222308579|%e %b %Y, %H:%M %Z|agohover
Solution: Problem1-30
siromasiroma 1222306078|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 1 / Solutions » Solution: Problem1-30

Part 1


1st law:

(1)
du=\delta{Q}+\delta{W}=Tds-Pdv

Enthalpy definition:

(2)
h=u+Pv

Enthalpy differential:

(3)
dh=du+Pdv+vdP=Tds+vdP

Maxwell equation from (2):

(4)
(\frac{\partial{T}}{\partial{P}})_v=(\frac{\partial{v}}{\partial{s}})_T

Definition of heat capacity and insertion (1) into definition:

(5)
c_v=(\frac{\partial{u}}{\partial{T}})_v=T(\frac{\partial{s}}{\partial{T}})_v

Write entropy as function of T and v:

(6)
s=s(T,v)

Derive expression for entropy differential and use (4) and (5):

(7)
ds=(\frac{\partial{s}}{\partial{T}})_vdT+(\frac{\partial{s}}{\partial{v}})_T=\frac{c_v}{T}dT+(\frac{\partial{P}}{\partial{T}})_vdv

Insert (7) into (1):

(8)
du=\delta{Q}+\delta{W}=Tds-Pdv=T(\frac{c_v}{T}dT+(\frac{\partial{P}}{\partial{T}})_vdv)-Pdv=(T(\frac{\partial{P}}{\partial{T}})_v -P)+c_vdT

QED

Part 2


van der Waals equation:

(9)
(p+\frac{a}{v^2})(v-b)=kT

Express p:

(10)
p=\frac{kT}{v-b}-\frac{a}{v^2}

At constant T equation (8) becomes:

(11)
(\frac{\partial{u}}{\partial{v}})_T=T(\frac{\partial{P}}{\partial{T}})_v-p

Differentiate (10) at constant v and put into (11):

(12)
T(\frac{\partial{P}}{\partial{T}})_v-p=\frac{kT}{v-b}-p=\frac{a}{v^2}

QED

Solution: Problem1-30 by siromasiroma, 1222306078|%e %b %Y, %H:%M %Z|agohover
Re: including pdf documents
juliantalbotjuliantalbot 1221818895|%e %b %Y, %H:%M %Z|agohover
in discussion General Forum / Discussion » including pdf documents
rsite1d.pdf
Re: including pdf documents by juliantalbotjuliantalbot, 1221818895|%e %b %Y, %H:%M %Z|agohover
including pdf documents
juliantalbotjuliantalbot 1221818281|%e %b %Y, %H:%M %Z|agohover
in discussion General Forum / Discussion » including pdf documents

pdf documents can be incorporated in posts.

including pdf documents by juliantalbotjuliantalbot, 1221818281|%e %b %Y, %H:%M %Z|agohover
solution
deepalideepali 1204398487|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 1 / Solutions » solution

can somebody post 1-51

solution by deepalideepali, 1204398487|%e %b %Y, %H:%M %Z|agohover
Re: Chapter 2 Questions
deepalideepali 1204398392|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 2 / Solutions » Chapter 2 Questions

can somebody post 2-2,2-6,2-11

Re: Chapter 2 Questions by deepalideepali, 1204398392|%e %b %Y, %H:%M %Z|agohover
Re: McQuarrie 1-24
subbareddysubbareddy 1196876116|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 1 / Solutions » McQuarrie 1-15

Does any one have solution for this?

Re: McQuarrie 1-24 by subbareddysubbareddy, 1196876116|%e %b %Y, %H:%M %Z|agohover
Problem 10,19,20
doufasdoufas 1196030824|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 4 / Solutions » Problem 10,19,20

Does anybody have thoughts on #s 10, 19, or 20?

Problem 10,19,20 by doufasdoufas, 1196030824|%e %b %Y, %H:%M %Z|agohover
Re: posting solutions
fizzixmomfizzixmom 1194977349|%e %b %Y, %H:%M %Z|agohover
in discussion General Forum / Discussion » posting solutions

Click on the

(1)
$\surd x$

(the "mathematical equation" button), then use LaTeX to type your equations.

If you are new to LaTeX, you can learn it quickly at [http://www.maths.tcd.ie/~dwilkins/LaTeXPrimer/]

Re: posting solutions by fizzixmomfizzixmom, 1194977349|%e %b %Y, %H:%M %Z|agohover
Re: Chapter 2 Questions
fizzixmomfizzixmom 1194976051|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 2 / Solutions » Chapter 2 Questions

I already turned my solutions in, but will try to post as soon as I get them back.

Re: Chapter 2 Questions by fizzixmomfizzixmom, 1194976051|%e %b %Y, %H:%M %Z|agohover
testing
fizzixmomfizzixmom 1194975936|%e %b %Y, %H:%M %Z|agohover
in discussion General Forum / Discussion » testing

I'm new to wikidot, and trying to figure out if I need to be a member to post a message. I guess we'll see if this works.

testing by fizzixmomfizzixmom, 1194975936|%e %b %Y, %H:%M %Z|agohover
Chapter 2 Questions
doufasdoufas 1194818707|%e %b %Y, %H:%M %Z|agohover
in discussion Chapter 2 / Solutions » Chapter 2 Questions

Does anybody know #2-2, 2-12 or 2-14?

Chapter 2 Questions by doufasdoufas, 1194818707|%e %b %Y, %H:%M %Z|agohover

does anybody knowthe solution for 5.7?

can anyone help me for the solution5.7 by kal-elkal-el, 1193677762|%e %b %Y, %H:%M %Z|agohover
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