Curl and Divergence (flux, and what not)

AI Thread Summary
The problem involves finding a vector field \(\vec{G}\) such that the curl of \(\vec{G}\) equals a given vector field \(\vec{F} = <y, z, x>\) under the condition that the divergence of \(\vec{F}\) is zero, indicating incompressibility. The discussion highlights the use of vector identities to simplify the expression, particularly focusing on the relationship between the components of \(\vec{G}\) and \(\vec{F}\). It is noted that expanding the cross product leads to a system of equations where components can be equated, allowing for the determination of \(\vec{G}\). The solution is confirmed to be non-unique, providing flexibility in the approach. Overall, the thread emphasizes the application of vector calculus identities in solving the problem.
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I'm having a bit of difficulty with this problem:
<br /> \vec{\nabla} \times \vec{G} = \vec{F}<br />
where
\vec{\nabla} \cdot \vec{F} = 0
and \vec{F} = &lt;y, z, x&gt;.
Find \vec{G}. I'm really at a loss how to solve this. I know the solution must be quick and easy because it was on a quiz. What I do know is this is called "incompressable" if, say it were a vector field of a fluid. Any help would be appreciated.
 
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You have:

\vec{\nabla}.(\vec{\nabla} \times \vec{G}) = 0

Can you expand the left hand side using a suitable vector identity?
 
http://astron.berkeley.edu/~jrg/ay202/node189.html ?

14.54 gives me the form, such that A = G, but does this mean B = F if I expanded to 14.51?
 
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Just a follow up incase someone else needed the same solution. Merely expanding the cross product (<P,Q,R> form as \vec{G}) leaves a vector in differentials that is equal to \vec{F}. From then its just a matter of setting the components equal to each other and knocking off which ever differential you would like. You can do this because the solution is not unique. Thanks for the help.
 
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