Recent content by patric44

OK, so you mean the pressure due to the weight of water contained at the z part (##\rho g h_{z}##) will act also along the right side affecting the area ##A_{y}## hence its force = ##\rho g h_{z} A_{y}##, am I correct in this interpretation. the confusing thing also is, if I use integration it...

I guess it will be ##\rho g h_{y}## but it will be a downward pressure.

Hi All, in the following problem: the book solution I don't understand why he added the term $$ \rho g h_{z} A_{y} $$ shouldn't it just be : $$ F = 1/2 \rho g h_{y} A_{y} $$

the folder of the ARPACK does not contain any folder named "arpacklib" is that the missing folder?where do i get it

the paper isn't open access so I thought I would write the question separably, here is the link of the paper: the paper, the commutation relation is included in the paper but i am not interested in proving them, rather my concern is equations 4a,4b,4c

Hi all I found this expression in a paper that concerns the derivation of some relations about boson operators but it is not very clear to me how the results were obtained. The derivation starts as, let B be an operator as a linear combination of different boson operators: $$...

hi all I am trying to install the ARPACK library for windows (another program needs the library for calculations) , I download a arpack96.tar.gz file that i found online , downloaded "make" and the mingw-gfortran and all that, modified the ARmake and the Makefile, but when i try the command...

Hi all I am trying to follow a derivation of something involving second quantization formalism, I am stuck at this step : $$ \sum_{m2}\sum_{\mu1} \bra{2,m1,2,m2}\ket{k,q}\bra{2,\mu1,2,\mu2}\ket{k,-q}\delta_{-m2,\mu1} = (-1)^{2+m2}\frac{\sqrt{2k+1}}{\sqrt{5}}\bra{k,-q,2,m2}\ket{2,-m1}\times...

hi all how do I prove that $$ <A^{n}>=<A>^{n} $$ It seems intuitive but how do I rigorously prove it, My attempt was like , the LHS can be written as: $$ \bra{\Psi}\hat{A}.\hat{A}.\hat{A}...\ket{\Psi}=\lambda^{n} \bra{\Psi}\ket{\Psi}=\lambda^{n}\delta_{ii}=\lambda^{n} $$ and the RHS equal: $$...

no problem bro no need to apologies, thanks for taking time to consider my question, I appreciate any help 😇

but why its not simply ##\omega=E/\hbar## then $$ \omega = (\hbar/2I) J(J+1) $$ why the differential definition

Hi all I am a little bit confused about the definition of angular frequency in the context of nuclear rotation, some times its defined in the regular way as $$ E=\hbar \omega $$ and other time from the rigid rotor formula $$ E=\frac{\hbar^{2}}{2I} J(J+1) $$ where ##I## is the moment of inertia...

##y## is the measured data ##\tilde{y}## is the calculated data from a specific model ##\delta y_i ## is the error in measuring ##y## ##m## the number of parameters of the model I am not talking about the so called category chi2. I mean the other one

Hi all I want to calculate the reduced Chi square and root mean square deviation RMSD of some data points that i have, but I am confused about the correct formula for each of them, which one is the correct one. I found this formula in a paper where they referred to it as the RMSD : $$...

the idea is that I want to determine the values of k,c for the specific model given by ##y=kx/(5+cx)##, because I will use the formula of the model in further calculations. from what I unstrood from you guys now I believe that the person who told me that the parameters vary could be mistaken or...