Need immediate help. Question in attachment from VECTOR CALCULUS.

Question

anonymous · Answer

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ganeshie8 · Answer

you may use divergence thm as it is a closed surface

jhannybean · Answer

Oh this is exactly what I am learning :)

ganeshie8 · Answer

$$\iint_S \vec{F}\cdot \vec{n}dS = \iiint_D \nabla \cdot \vec{F} dV$$

anonymous · Answer

Divergence I haven't learnt yet. I know Stoke's and Green's. Next week i will learn Divergence.. And the teacher said to use Stoke. 
I am not being able to find the normal vector to the surface..
Oh in divergence we have direct formula.:O

ganeshie8 · Answer

yes you can derive divergence theorem from stokes theorem

anonymous · Answer

please tell me how to find the unit normal, next week after learning divergence, i will surely try this sum using Gauss divergence theorem. But for now I should not use it. @ganeshie8

jhannybean · Answer

$$\vec n = \frac{ \nabla f }{\sqrt{ |\nabla f| }}$$

anonymous · Answer

@Jhannybean  the surface is given as the surface bdd by the planes x=0,x=1;y=0,y=1,z=0,z=1 which is a cube .. How to get the expression for f?

jhannybean · Answer

I'm kind of new on this topic as well...

anonymous · Answer

I dont think so.. @Jhannybean

ganeshie8 · Answer

your surface just contains a set of 6 planes, right ?

anonymous · Answer

yes...

ganeshie8 · Answer

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ganeshie8 · Answer

unit normals are just the unit vectors ^

ganeshie8 · Answer

unit normals for front and back faces :  $\hat{i}, -\hat{i}$

anonymous · Answer

you are considering the projection on the yz plane?

ganeshie8 · Answer

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