Applying Stokes' Theorem in Spherical Coordinates

In summary, the conversation discusses the use of Stokes' theorem and a change of variables to solve a problem involving the integral of a vector field over a region. The speaker is unsure of how to define the functions and partials for the change of variables, but is seeking clarification in order to better understand the concept. They also mention watching a video for guidance and questioning if their approach can be done in spherical coordinates.
  • #1
BiGyElLoWhAt
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OK, so I know stokes theorem states that I can turn ##\int \int_{S}F\cdot dS## into ##\int \int (-P\frac{\partial g(x,y)}{\partial x} -Q\frac{\partial g(x,y)}{\partial y} + R)dxdy##

but I have a problem that I'm working on that's screaming change of variables (to spherical), but I'm not sure if I can apply stokes' this way...

my region is ##x^2 +y^2 + z^2 = 64##, and I really want to make my region a spherical region (if possible, as I need to understand this for my final) but I'm not sure how to define g.

What's throwing me off is which partials to take. My F is ##<x,-y,z>## and upon making the proper substitutions, ##- \rho <cos(\theta )sin(\phi ), -sin(\theta )sin(\phi ), cos(\ phi)>##
and I suppose g would be ##\rho <cos(\theta )sin(\phi ), sin(\theta )sin(\phi ), cos(\ phi)>## , since that's my region? It's the region in the first quadrant oriented inwards, that's where the negative sign came from, I guess it should probably be in g, but either way it's going make it into the integral.

But now, how do I define my g and my partials? I understand P is my ##\hat{i}## and Q j and R z, but I'm uncertain as to which partials I'm multiplying by which functions.

I'm not sure if I can even do this, I'm just trying to understand this better. any help would be greatly appreciated =]
 
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  • #2
Ok, I didn't want to, but I watched the "how to" video, which basically works through the problem, and they ended up solving "g" for z, but I'm still wondering if there is a way to do this in spherical? Or do I need ##F = P\hat{\theta} + Q \hat{\phi} + R \hat{\rho}## in order to make this work like I'm wanting it to?
 

1. What is Stokes' Theorem?

Stokes' Theorem is a mathematical theorem that relates the surface integral of a vector field over a surface to the line integral of the same vector field around the boundary of the surface.

2. Why is Stokes' Theorem important?

Stokes' Theorem is important because it is a fundamental tool in vector calculus and is used to solve a variety of problems in physics and engineering. It also provides a link between the line integral and surface integral, making it a powerful tool for solving complex problems.

3. How is Stokes' Theorem derived?

Stokes' Theorem is derived from the fundamental theorem of calculus and the divergence theorem. It can also be thought of as a higher-dimensional version of Green's Theorem.

4. What are the assumptions of Stokes' Theorem?

The main assumptions of Stokes' Theorem are that the surface is smooth and bounded, and the vector field is continuous and differentiable on the surface.

5. How is Stokes' Theorem used in real-world applications?

Stokes' Theorem is used in a variety of real-world applications, including fluid dynamics, electromagnetism, and computer graphics. It is also used in the study of weather patterns and ocean currents, as well as in the design of aircraft and other complex systems.

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