Divergence Theorem Homework: Volume & Surface Integral

[athrun200]

Homework Statement

Homework Equations

The Attempt at a Solution

I can get the answer after applying divergence theorem to have a volume integral.

But how about about the surface integral?
It seems the 4 points given can't form a surface.

 

[Office_Shredder]

It seems the 4 points given can't form a surface.

Don't confuse a surface with a plane. The surface of the cube is all six of its sides

 

[LCKurtz]

Homework Statement

Homework Equations

The Attempt at a Solution

I can get the answer after applying divergence theorem to have a volume integral.

But how about about the surface integral?
It seems the 4 points given can't form a surface.

Those four points don't form a cube either. The problem doesn't imply that they do either. But the problem says a cube includes those four vertices, and that is enough to determine the cube. Presumably you knew that otherwise how did you apply the divergence theorem? It's the surface of that cube you need to use.

 

[HallsofIvy]

I don't believe that Office Shredder meant to imply that it was a cube- he was only giving that as an example. His point was what you said- that every solid has a surface (not necessarily smooth) as boundary. Here, the surface is made of four planes.

 

[LCKurtz]

I don't believe that Office Shredder meant to imply that it was a cube- he was only giving that as an example. His point was what you said- that every solid has a surface (not necessarily smooth) as boundary. Here, the surface is made of four planes.

If you are addressing that to me, I was neither quoting nor replying to Office Shredder. The original post clearly refers to the cube containing those four vertices, not a tetrahedron, and the OP was apparently missing that when trying to figure out the surface.

 

[hunt_mat]

Well, you know that a cube has 6 sides that are the same, so from the the information given you should be able to construct the cube from that.