- #1

Urmi Roy

- 753

- 1

1.divergence is supposed to be the

__flux per unit volume at a particular point__...again,I saw on wikipedia,that they define divergence as

__"the derivative of net flow of of the vector field across surface of a small region relative to the volume of the region...I can't see how these two defineitions are equivalent.__

2. The word 'flow' is used in the above definition...all vectors however can't have 'flow',like the displacement vector for example...right?

3.I found on a website, an example illustrating divergence...it said, that for a particular vector field,the change of the vector along x axis,y axis and z axis were 1,-2,3...subsequently,the author calculated the divergence as 1-2+3=2...how can the divergence be obtained

*just like that*? I don't understand.

4.As I said,the divergence is the volume density of flux...however,in the

__formulation of the divergence in terms of the del operator does not include 'volume' anywhere...please explain.__

5. Again,the

__divergence is said to be a measure of the expansion of a vector field at a point__,but the notion of divergence as "volume density of flux" does not seem to indicate any 'expansion'.

6. The point itself at which the divergence is being measured

__may not be a source or sink of flux__...a vector might just be passing the point...right?

Sorry for asking so many questions! I need to get my head around this.