Curl of a field in spherical polar coordinates

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SUMMARY

The discussion centers on finding the scalar function wφ(r,θ) in spherical polar coordinates, given that the curl of the vector field w = wφ(r,θ)eφ is zero. The user attempts to derive a potential function for w by evaluating the curl using the determinant method, which involves partial derivatives with respect to r, θ, and φ. Despite correctly setting up the equations, the user encounters difficulties in solving the resulting partial differential equations due to a lack of initial conditions and instruction on the solution methods.

PREREQUISITES
  • Understanding of vector calculus, specifically curl in curvilinear coordinates.
  • Familiarity with spherical polar coordinates and their unit vectors (er, eθ, eφ).
  • Knowledge of partial differential equations and their solutions.
  • Basic proficiency in using determinants for vector calculus operations.
NEXT STEPS
  • Study the derivation and application of the curl in spherical coordinates.
  • Learn methods for solving partial differential equations, particularly separation of variables.
  • Explore potential theory in vector fields to understand the implications of curl being zero.
  • Review the vector identities in curvilinear coordinates for further insights into vector calculus.
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Students and professionals in physics and engineering, particularly those focusing on fluid dynamics, electromagnetism, and advanced calculus involving vector fields.

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Homework Statement


I have a field w=wφ(r,θ)eφ^ (e^ is supposed to be 'e hat', a unit vector)
Find wφ(r,θ) given the curl is zero and find a potential for w.

Homework Equations


I can't type the matrix for curl in curvilinear, don't even know where to start! I've been given it in the form ##\frac{1}{r^2 sin(\theta)}## multiplied by a determinant with top row:
er^, reθ^, rsin(θ) eφ^

Second row:
∂/∂r, ∂/∂θ, ∂/∂φ

Third row:
ar, raθ, rsin(θ)aφ

The Attempt at a Solution


ar, raθ = 0 and my aφ is wφ. So I'm left with

##\frac{1}{r^2 sin(\theta)}## ∂(wφrsin(θ)er^)/∂θ - ##\frac{1}{r^2 sin(\theta)}##(reθ^)∂(wφrsin(θ))/∂r

So I evaluated the partial derivatives, set each individual component to zero and get a partial differential equation. We have not been taught how to solve these, so I can only assume it's the wrong method... I gave it a go as the two equations are separable but they don't give w as a function of r and θ and I have no initial conditions to find c with!

After differentiating I had:
[rcos(θ)wφ + rsin(θ) ∂wφ/∂θ] er^ - reθ^ [sin(θ)wφ + rsinθ ∂wφ/∂r] all multiplied by ##\frac{1}{r^2 sin(\theta)}## And both components should individually equal zero, I think.
 
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