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A problem about surface element 
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#1
Feb1613, 12:17 PM

P: 58

I really don't know how to do this question as it asks me to write the surface element of a hemisphere in xyz coordinates. I know how to answer if it is asked in spherical coordinates.
I think this is a tricky question because it asks for the portion da near (0, A, 0) (in xyz) where A is the radius. I guess da = dydz. 


#2
Feb1613, 12:37 PM

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You say you know the answer in spherical coordinates. What is the answer in spherical coordinates? 


#3
Feb1613, 12:38 PM

P: 58




#4
Feb1613, 12:41 PM

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A problem about surface element



#5
Feb1613, 12:45 PM

P: 58

so i should plug this valve to the expression? i have tried but the question needs me to express it in xyz coor, how to deal with (unit vector of r)? 


#6
Feb1613, 12:57 PM

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#7
Feb1613, 01:14 PM

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O, I get what u mean
at (0 A 0) , the r is along the y axis, so 0i, 1j , 0k ? 


#8
Feb1613, 01:43 PM

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