X-Git-Url: https://hackdaworld.org/gitweb/?p=lectures%2Flatex.git;a=blobdiff_plain;f=physics_compact%2Fmath_app.tex;h=4f7822e61b3162d17763f780c71369a7e0e97e65;hp=ec21dae694d53792baf78ca3b974897cb3a1dacd;hb=eac23ae428984d20c62851681234b206ec1e3dc7;hpb=147329059cdda2ebf293426b7fdbcd13b0c783f9 diff --git a/physics_compact/math_app.tex b/physics_compact/math_app.tex index ec21dae..4f7822e 100644 --- a/physics_compact/math_app.tex +++ b/physics_compact/math_app.tex @@ -180,13 +180,19 @@ holds. \section{Spherical coordinates} -Cartesian coordinates $\vec{r}(x,y,z)$ are related to spherical coordinates $\vec{r}(r,\theta,\phi)$ by +Cartesian coordinates $\vec{r}(x,y,z)$ are related to spherical coordinates $\vec{\tilde{r}}(r,\theta,\phi)$ by \begin{eqnarray} -x&=&r\sin\theta\cos\phi\textrm{ ,}\\ -y&=&r\sin\theta\sin\phi\textrm{ ,}\\ -z&=&r\cos\theta\textrm{ .} +x&=&r\sin\theta\cos\phi\\ +y&=&r\sin\theta\sin\phi\\ +z&=&r\cos\theta \end{eqnarray} -Infinitesimal translations $dq_i$ and $dq'_i$ of the two coordinate systems are related by the partial derivatives. +and +\begin{eqnarray} +r&=&(x^2+y^2+z^2)^{1/2}\\ +\theta&=&\arccos(z/r)\\ +\phi&=&\arctan(y/x) +\end{eqnarray} +The total differentials $dq_i$ and $dq'_i$ of two coordinate systems are related by partial derivatives. \begin{equation} dq_i=\sum_j \frac{\partial q_i}{\partial q'_j}dq'_j \end{equation} @@ -198,7 +204,7 @@ J_{ij}=\frac{\partial q_i}{\partial q'_j} is called the Jacobi matrix. \end{definition} -For cartesian and spherical coordinates the relation of the translations are presented in detail +For cartesian and spherical coordinates the relation of the translations are \begin{eqnarray} dx&=&\frac{\partial x}{\partial r}dr + \frac{\partial x}{\partial \theta}d\theta + @@ -210,17 +216,29 @@ dz&=&\frac{\partial z}{\partial r}dr + \frac{\partial z}{\partial \theta}d\theta + \frac{\partial z}{\partial \phi}d\phi\\ \end{eqnarray} -and the vector consisting of all or using the Jacobi matrix - - +and +\begin{eqnarray} +dr&=&\frac{\partial r}{\partial x}dx + + \frac{\partial r}{\partial y}dy + + \frac{\partial r}{\partial z}dz\\ +d\theta&=&\frac{\partial \theta}{\partial x}dx + + \frac{\partial \theta}{\partial y}dy + + \frac{\partial \theta}{\partial z}dz\\ +d\phi&=&\frac{\partial \phi}{\partial x}dx + + \frac{\partial \phi}{\partial y}dy + + \frac{\partial \phi}{\partial z}dz\\ +\end{eqnarray} +and vectorial translations using the Jacobi matrix are given by matrix multiplications +\begin{equation} +d\vec{r}(x,y,z)=Jd\vec{\tilde{r}}(r,\theta,\phi) +\end{equation} +and +\begin{equation} +d\vec{\tilde{r}}(r,\theta,\phi)=J^{-1}d\vec{r}(x,y,z) \text{ .} +\end{equation} +$J$ and $J^{-1}$ are explicitily given by \begin{equation} - =\sin\theta\cos\phi dr + \\ \end{equation} - -To obtain infinitesimal -\begin{definition}[Jacobi matrix] - -\end{definition} \section{Fourier integrals}