Vektorske operacije u zakrivljenim koordinatama

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Ovo je popis najbitnijih relacija i operacija vektorskog računa u sfernom, cilindričnom, paraboličnom i kartezijevu sustavu.

Operacija Kartezijeve koordinate (x,y,z) Cilindrične koordinate (ρ,φ,z) Sferne koordinate (r,ϑ,φ) Parabolične koordinate (σ,τ,z)
Definicija
koordinata
\begin{matrix}
    \rho & = & \sqrt{x^2+y^2} \\
    \varphi & = & \arctan(y/x) \\
       z & = & z \end{matrix} \begin{matrix}
    x & = & \rho\cos\varphi \\
    y & = & \rho\sin\varphi \\
    z & = & z \end{matrix} \begin{matrix}
    x & = & r\sin\vartheta\cos\varphi \\
    y & = & r\sin\vartheta\sin\varphi \\
    z & = & r\cos\vartheta \end{matrix} \begin{matrix}
    x & = & \sigma \tau\\
    y & = & \frac{1}{2} \left( \tau^{2} - \sigma^{2} \right) \\
    z & = & z \end{matrix}
\begin{matrix}
    r      & = & \sqrt{x^2+y^2+z^2} \\
    \vartheta & = & \arccos(z/r)\\
    \varphi   & = & \arctan(y/x) \\ \end{matrix} \begin{matrix}
    r      & = & \sqrt{\rho^2 + z^2} \\
    \vartheta & = & \arctan{(\rho/z)}\\
    \varphi   & = & \varphi \end{matrix} \begin{matrix}
    \rho & = & r\sin(\vartheta) \\
    \varphi & = & \varphi\\
    z    & = & r\cos(\vartheta) \end{matrix} \begin{matrix}
    \rho\cos\varphi & = & \sigma \tau\\
    \rho\sin\varphi & = & \frac{1}{2} \left( \tau^{2} - \sigma^{2} \right) \\
    z & = & z \end{matrix}
Definicija
jediničnih
vektora
\begin{matrix}
    \boldsymbol{\hat \rho} & = &  \frac{x}{\rho}\mathbf{\hat x}+\frac{y}{\rho}\mathbf{\hat y} \\
    \boldsymbol{\hat\varphi} & = & -\frac{y}{\rho}\mathbf{\hat x}+\frac{x}{\rho}\mathbf{\hat y} \\
    \mathbf{\hat z}       & = &  \mathbf{\hat z}
    \end{matrix} \begin{matrix}
    \mathbf{\hat x} & = & \cos\varphi\boldsymbol{\hat \rho}-\sin\varphi\boldsymbol{\hat\varphi} \\
    \mathbf{\hat y} & = & \sin\varphi\boldsymbol{\hat \rho}+\cos\varphi\boldsymbol{\hat\varphi} \\
    \mathbf{\hat z} & = & \mathbf{\hat z}
    \end{matrix} \begin{matrix}
    \mathbf{\hat x} & = & \sin\vartheta\cos\varphi\boldsymbol{\hat r}+\cos\vartheta\cos\varphi\boldsymbol{\hat\vartheta}-\sin\varphi\boldsymbol{\hat\varphi} \\
    \mathbf{\hat y} & = & \sin\vartheta\sin\varphi\boldsymbol{\hat r}+\cos\vartheta\sin\varphi\boldsymbol{\hat\vartheta}+\cos\varphi\boldsymbol{\hat\varphi} \\
    \mathbf{\hat z} & = & \cos\vartheta        \boldsymbol{\hat r}-\sin\vartheta        \boldsymbol{\hat\vartheta} \\
    \end{matrix} \begin{matrix}
    \boldsymbol{\hat \sigma} & = &  \frac{\tau}{\sqrt{\tau^2+\sigma^2}}\mathbf{\hat x}-\frac{\sigma}{\sqrt{\tau^2+\sigma^2}}\mathbf{\hat y} \\
    \boldsymbol{\hat\tau} & = &  \frac{\sigma}{\sqrt{\tau^2+\sigma^2}}\mathbf{\hat x}+\frac{\tau}{\sqrt{\tau^2+\sigma^2}}\mathbf{\hat y} \\
    \mathbf{\hat z}       & = &  \mathbf{\hat z}
    \end{matrix}
\begin{matrix}
    \mathbf{\hat r}         & = & \frac{x\mathbf{\hat x}+y\mathbf{\hat y}+z\mathbf{\hat z}}{r} \\
    \boldsymbol{\hat\vartheta} & = & \frac{xz\mathbf{\hat x}+yz\mathbf{\hat y}-\rho^2\mathbf{\hat z}}{r \rho} \\
    \boldsymbol{\hat\varphi}   & = & \frac{-y\mathbf{\hat x}+x\mathbf{\hat y}}{\rho}
    \end{matrix} \begin{matrix}
    \mathbf{\hat r}         & = & \frac{\rho}{r}\boldsymbol{\hat \rho}+\frac{   z}{r}\mathbf{\hat z} \\
    \boldsymbol{\hat\vartheta} & = & \frac{z   }{r}\boldsymbol{\hat \rho}-\frac{\rho}{r}\mathbf{\hat z} \\
    \boldsymbol{\hat\varphi}   & = & \boldsymbol{\hat\varphi}
    \end{matrix} \begin{matrix}
    \boldsymbol{\hat \rho} & = & \sin\vartheta\mathbf{\hat r}+\cos\vartheta\boldsymbol{\hat\vartheta} \\
    \boldsymbol{\hat\varphi} & = & \boldsymbol{\hat\varphi} \\
    \mathbf{\hat z}       & = & \cos\vartheta\mathbf{\hat r}-\sin\vartheta\boldsymbol{\hat\vartheta} \\
    \end{matrix} \begin{matrix}
    \end{matrix}
A vektorsko polje \mathbf{A} A_x\mathbf{\hat x} + A_y\mathbf{\hat y} +
A_z\mathbf{\hat z} A_\rho\boldsymbol{\hat \rho} +
A_\varphi\boldsymbol{\hat \varphi} + A_z\boldsymbol{\hat z} A_r\boldsymbol{\hat r} + A_\vartheta\boldsymbol{\hat
\vartheta} + A_\varphi\boldsymbol{\hat \varphi} A_\sigma\boldsymbol{\hat \sigma} +
A_\tau\boldsymbol{\hat \tau} + A_\varphi\boldsymbol{\hat z}
Gradijent \nabla f {\partial f \over \partial x}\mathbf{\hat x} + {\partial
f \over \partial y}\mathbf{\hat y}
  + {\partial f \over \partial z}\mathbf{\hat z} {\partial f \over \partial \rho}\boldsymbol{\hat \rho}
  + {1 \over \rho}{\partial f \over \partial \varphi}\boldsymbol{\hat \varphi}
  + {\partial f \over \partial z}\boldsymbol{\hat z} {\partial f \over \partial r}\boldsymbol{\hat r}
  + {1 \over r}{\partial f \over \partial \vartheta}\boldsymbol{\hat \vartheta}
  + {1 \over r\sin\vartheta}{\partial f \over \partial \varphi}\boldsymbol{\hat \varphi}  \frac{1}{\sqrt{\sigma^{2} + \tau^{2}}} {\partial f
\over \partial \sigma}\boldsymbol{\hat \sigma} +
\frac{1}{\sqrt{\sigma^{2} + \tau^{2}}} {\partial f \over \partial
\tau}\boldsymbol{\hat \tau} + {\partial f \over \partial
z}\boldsymbol{\hat z}
Divergencija \nabla \cdot \mathbf{A} {\partial A_x \over \partial x} + {\partial A_y \over
\partial y} + {\partial A_z \over \partial z} {1 \over \rho}{\partial \left( \rho A_\rho  \right)
\over \partial \rho}
  + {1 \over \rho}{\partial A_\varphi \over \partial \varphi}
  + {\partial A_z \over \partial z} {1 \over r^2}{\partial \left( r^2 A_r \right) \over
\partial r}
  + {1 \over r\sin\vartheta}{\partial \over \partial \vartheta} \left(  A_\vartheta\sin\vartheta \right)
  + {1 \over r\sin\vartheta}{\partial A_\varphi \over \partial \varphi}  \frac{1}{\sigma^{2} + \tau^{2}}{\partial A_\sigma \over
\partial \sigma} + \frac{1}{\sigma^{2} + \tau^{2}}{\partial A_\tau
\over \partial \tau} + {\partial A_z \over \partial z}
Rotacija \nabla \times \mathbf{A} \begin{matrix}
  \displaystyle\left({\partial A_z \over \partial y} - {\partial A_y \over \partial z}\right) \mathbf{\hat x} & + \\
  \displaystyle\left({\partial A_x \over \partial z} - {\partial A_z \over \partial x}\right) \mathbf{\hat y} & + \\
  \displaystyle\left({\partial A_y \over \partial x} - {\partial A_x \over \partial y}\right) \mathbf{\hat z} & \ \end{matrix} \begin{matrix}
  \displaystyle\left({1 \over \rho}{\partial A_z \over \partial \varphi}
    - {\partial A_\varphi \over \partial z}\right) \boldsymbol{\hat \rho} & + \\
  \displaystyle\left({\partial A_\rho \over \partial z} - {\partial A_z \over \partial \rho}\right) \boldsymbol{\hat \varphi} & + \\
  \displaystyle{1 \over \rho}\left({\partial \left( \rho A_\varphi \right) \over \partial \rho}
    - {\partial A_\rho \over \partial \varphi}\right) \boldsymbol{\hat z} & \ \end{matrix} \begin{matrix}
  \displaystyle{1 \over r\sin\vartheta}\left({\partial \over \partial \vartheta} \left( A_\varphi\sin\vartheta \right)
    - {\partial A_\vartheta \over \partial \varphi}\right) \boldsymbol{\hat r} & + \\
  \displaystyle{1 \over r}\left({1 \over \sin\vartheta}{\partial A_r \over \partial \varphi}
    - {\partial \over \partial r} \left( r A_\varphi \right) \right) \boldsymbol{\hat \vartheta} & + \\
  \displaystyle{1 \over r}\left({\partial \over \partial r} \left( r A_\vartheta \right)
    - {\partial A_r \over \partial \vartheta}\right) \boldsymbol{\hat \varphi} & \ \end{matrix} \begin{matrix}
  \displaystyle\left(\frac{1}{\sqrt{\sigma^{2} + \tau^{2}}}{\partial A_z \over \partial \tau}
    - {\partial A_\tau \over \partial z}\right) \boldsymbol{\hat \sigma} & - \\
  \displaystyle\left(\frac{1}{\sqrt{\sigma^{2} + \tau^{2}}}{\partial A_z \over \partial \sigma}- {\partial A_\sigma \over \partial z}\right) \boldsymbol{\hat \tau} & + \\
  \displaystyle\frac{1}{\sqrt{\sigma^{2} + \tau^{2}}}\left({\partial \left( \rho A_\varphi \right) \over \partial \rho}
    - {\partial A_\rho \over \partial \varphi}\right) \boldsymbol{\hat z} & \ \end{matrix}
Laplasijan \Delta f = \nabla^2 f {\partial^2 f \over \partial x^2} + {\partial^2 f \over
\partial y^2} + {\partial^2 f \over \partial z^2} {1 \over \rho}{\partial \over \partial \rho}\left(\rho
{\partial f \over \partial \rho}\right)
  + {1 \over \rho^2}{\partial^2 f \over \partial \varphi^2}
  + {\partial^2 f \over \partial z^2} {1 \over r^2}{\partial \over \partial r}\!\left(r^2
{\partial f \over \partial r}\right)
  \!+\!{1 \over r^2\!\sin\vartheta}{\partial \over \partial \vartheta}\!\left(\sin\vartheta {\partial f \over \partial \vartheta}\right)
  \!+\!{1 \over r^2\!\sin^2\vartheta}{\partial^2 f \over \partial \varphi^2}  \frac{1}{\sigma^{2} + \tau^{2}} \left(
\frac{\partial^{2} f}{\partial \sigma^{2}} + \frac{\partial^{2}
f}{\partial \tau^{2}} \right) + \frac{\partial^{2} f}{\partial
z^{2}}
Vekotrski laplasijan \Delta
\mathbf{A} = \nabla^2 \mathbf{A} \Delta A_x \mathbf{\hat x} + \Delta A_y \mathbf{\hat y}
+ \Delta A_z \mathbf{\hat z} \begin{matrix}
  \displaystyle\left(\Delta A_\rho - {A_\rho \over \rho^2}
    - {2 \over \rho^2}{\partial A_\varphi \over \partial \varphi}\right) \boldsymbol{\hat \rho} & + \\
  \displaystyle\left(\Delta A_\varphi - {A_\varphi \over \rho^2}
    + {2 \over \rho^2}{\partial A_\rho \over \partial \varphi}\right) \boldsymbol{\hat\varphi} & + \\
  \displaystyle\left(\Delta A_z \right) \boldsymbol{\hat z}  & \ \end{matrix} \begin{matrix}
  \left(\Delta A_r - {2 A_r \over r^2}
    - {2 \over r^2\sin\vartheta}{\partial \left(A_\vartheta \sin\vartheta\right) \over \partial\vartheta}
    - {2 \over r^2\sin\vartheta}{\partial A_\varphi \over \partial \varphi}\right) \boldsymbol{\hat r} & + \\
  \left(\Delta A_\vartheta - {A_\vartheta \over r^2\sin^2\vartheta}
    + {2 \over r^2}{\partial A_r \over \partial \vartheta}
    - {2 \cos\vartheta \over r^2\sin^2\vartheta}{\partial A_\varphi \over \partial \varphi}\right) \boldsymbol{\hat\vartheta} & + \\
  \left(\Delta A_\varphi - {A_\varphi \over r^2\sin^2\vartheta}
    + {2 \over r^2\sin\vartheta}{\partial A_r \over \partial \varphi}
    + {2 \cos\vartheta \over r^2\sin^2\vartheta}{\partial A_\vartheta \over \partial \varphi}\right) \boldsymbol{\hat\varphi} & \end{matrix}
Element duljine d\mathbf{l} = dx\mathbf{\hat x} + dy\mathbf{\hat y} +
dz\mathbf{\hat z} d\mathbf{l} = d\rho\boldsymbol{\hat \rho} + \rho
d\varphi\boldsymbol{\hat \varphi} + dz\boldsymbol{\hat z} d\mathbf{l} = dr\mathbf{\hat r} +
rd\vartheta\boldsymbol{\hat \vartheta} + r\sin\vartheta
d\varphi\boldsymbol{\hat \varphi} d\mathbf{l} = \sqrt{\sigma^{2} + \tau^{2}}
d\sigma\boldsymbol{\hat \sigma} + \sqrt{\sigma^{2} + \tau^{2}}
d\tau\boldsymbol{\hat \tau} + dz\boldsymbol{\hat z}
Element površine \begin{matrix}d\mathbf{S} = &dy\,dz\,\mathbf{\hat x} + \\
&dx\,dz\,\mathbf{\hat y} + \\
&dx\,dy\,\mathbf{\hat z}\end{matrix} \begin{matrix}
d\mathbf{S} = & \rho\, d\varphi\, dz\,\boldsymbol{\hat \rho} + \\
& d\rho \,dz\,\boldsymbol{\hat \varphi} + \\
& \rho \,d\rho d\varphi \,\mathbf{\hat z}
\end{matrix} \begin{matrix}
d\mathbf{S} = & r^2 \sin\vartheta \,d\vartheta \,d\varphi \,\mathbf{\hat r} + \\
& r\sin\vartheta \,dr\,d\varphi \,\boldsymbol{\hat \vartheta} + \\
& r\,dr\,d\vartheta\,\boldsymbol{\hat \varphi}
\end{matrix} \begin{matrix}
d\mathbf{S} = & \sqrt{\sigma^{2} + \tau^{2}}, d\tau\, dz\,\boldsymbol{\hat \sigma} + \\
& \sqrt{\sigma^{2} + \tau^{2}} d\sigma\,dz\,\boldsymbol{\hat \tau} + \\
& \sigma^{2} + \tau^{2} d\sigma, d\tau \,\mathbf{\hat z}
\end{matrix}
Element obujma dV = dx\,dy\,dz \, dV = \rho\, d\rho\, d\varphi\, dz\, dV = r^2\sin\vartheta \,dr\,d\vartheta\,
d\varphi\, dV = \left( \sigma^{2} + \tau^{2} \right) d\sigma d\tau
dz,
Netrivijalne kombinacije vektorskih operacija:
  1. \operatorname{div\ grad\ } f = \nabla \cdot (\nabla f) = \nabla^2 f = \Delta f (laplasijan)
  2. \operatorname{rot\ grad\ } f = \nabla \times (\nabla f) = \mathbf{0}
  3. \operatorname{div\ rot\ } \mathbf{A} = \nabla \cdot (\nabla \times \mathbf{A}) = 0
  4. \operatorname{rot\ rot\ } \mathbf{A} = \nabla \times (\nabla \times \mathbf{A})
                                                = \nabla (\nabla \cdot \mathbf{A}) - \nabla^2 \mathbf{A}
  5. \Delta f g = f \Delta g + 2 \nabla f \cdot \nabla g + g\Delta f

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