Parametrize sphere for Stoke's Thm

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Homework Statement



compute the flux of \stackrel{\rightarrow}{F} = <x,y,z> through the sphere x^{2} + y^{2} + z^{2} = 1

Homework Equations

\int\int_{S}Curl(\stackrel{\rightarrow}{F})\bullet ds = \int_{C}\stackrel{\rightarrow}{F}\bullet d\vec{r}

The Attempt at a Solution



I am having trouble parametrizing the surface S (the sphere of radius 1). I know I have to find a normal vector for the surface (which I know intuitivley is <x,y,z>) but I don't know how to get there if I have a different problem that is not so easy to see.

I tried parametrizing it in Spherical cordinates using two angles (\phi, \vartheta. Then I get for parametrzed equation

x = sin(\phi)cos(\vartheta)
y = sin(\phi)sin(\vartheta)
z = cos(\phi)

which gives the Normal vector as

n = &lt; sin^{2}(\phi)cos(\vartheta), -sin^{2}(\phi)sin(\vartheta), cos(\phi)sin(\phi) &gt;

This isn't right obviously...
How am I suposed to parametrize a function in such as the ball?

Thanks
 
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OK I found out what I needed...I was actualy mostly correct, aside from small computation errors :) Thanks anyway though
 
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