foxjwill
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[SOLVED] Vector, cross product, and integral
Evaluate:
[tex]{\int \textbf{F} \times \texttt{d}\textbf{v}}.[/tex]
[tex]\textbf{F}[/tex] and [tex]\textbf{v}[/tex] are both vector fields in [tex]\mathbb{R}^3[/tex]
[tex]\texttt{d}\textbf{v} = (\nabla \otimes \textbf{v} ) \texttt{d}\textbf{r}[/tex]
[tex] \begin{array}{ll}<br /> \textbf{F} \times \texttt{d}{\textbf{v}} &= \left( {<br /> \begin{array}{c}<br /> {F_2 \texttt{d}v_3 - F_3 \texttt{d}v_2 } \\<br /> {F_1 \texttt{d}v_2 - F_2 \texttt{d}v_1 } \\<br /> {F_1 \texttt{d}v_3 - F_3 \texttt{d}v_1 } \\<br /> \end{array}<br /> \right ) \\ <br /> &= \left( <br /> \begin{array}{c}<br /> {F_2 \nabla v_3 \cdot \texttt{d}{\textbf{r}} - F_3 \nabla v_3 \cdot \texttt{d}{\textbf{r}}} \\<br /> {F_1 \nabla v_2 \cdot \texttt{d}{\textbf{r}} - F_2 \nabla v_1 \cdot \texttt{d}{\textbf{r}}} \\<br /> {F_1 \nabla v_3 \cdot \texttt{d}{\textbf{r}} - F_3 \nabla v_1 \cdot \texttt{d}{\textbf{r}}} \\<br /> \end{array} \right) \\ <br /> \end{array}[/tex]
This can then be solved as three path integrals over some path [tex]\textbf{r}[/tex]. Is this correct?
Homework Statement
Evaluate:
[tex]{\int \textbf{F} \times \texttt{d}\textbf{v}}.[/tex]
[tex]\textbf{F}[/tex] and [tex]\textbf{v}[/tex] are both vector fields in [tex]\mathbb{R}^3[/tex]
Homework Equations
[tex]\texttt{d}\textbf{v} = (\nabla \otimes \textbf{v} ) \texttt{d}\textbf{r}[/tex]
The Attempt at a Solution
[tex] \begin{array}{ll}<br /> \textbf{F} \times \texttt{d}{\textbf{v}} &= \left( {<br /> \begin{array}{c}<br /> {F_2 \texttt{d}v_3 - F_3 \texttt{d}v_2 } \\<br /> {F_1 \texttt{d}v_2 - F_2 \texttt{d}v_1 } \\<br /> {F_1 \texttt{d}v_3 - F_3 \texttt{d}v_1 } \\<br /> \end{array}<br /> \right ) \\ <br /> &= \left( <br /> \begin{array}{c}<br /> {F_2 \nabla v_3 \cdot \texttt{d}{\textbf{r}} - F_3 \nabla v_3 \cdot \texttt{d}{\textbf{r}}} \\<br /> {F_1 \nabla v_2 \cdot \texttt{d}{\textbf{r}} - F_2 \nabla v_1 \cdot \texttt{d}{\textbf{r}}} \\<br /> {F_1 \nabla v_3 \cdot \texttt{d}{\textbf{r}} - F_3 \nabla v_1 \cdot \texttt{d}{\textbf{r}}} \\<br /> \end{array} \right) \\ <br /> \end{array}[/tex]
This can then be solved as three path integrals over some path [tex]\textbf{r}[/tex]. Is this correct?