Scale factors and the Jacobian Matrix

AI Thread Summary
The discussion focuses on the challenge of using non-Cartesian coordinates in mechanics, specifically regarding the relationship between scale factors and the Jacobian matrix. It is confirmed that the scale factor can be derived from the determinant of the Jacobian matrix, which consists of the first partial derivatives of the components in different coordinate systems. The conversation suggests that this method could potentially simplify the transition between coordinate frames. Additionally, it highlights the need for a more straightforward approach to convert expressions from one coordinate system to another. Understanding these relationships is crucial for effectively applying Lagrangian and Hamiltonian mechanics in curvilinear coordinates.
Andromon
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So here is my problem: I'm very bad when using coordinates others than cartesian ones, and I know taking Mechanics of Lagrange and Hamilton and I fin difficult to find the velocities expressions in curvilinear coordinates.

So here is my question: is there anyway to relate the scale factors (and everything else, from radius vector expression to operators expressoins) just using the Jacobian or derivates matrix? Like you can do in Thermodynamics

I have not seen it done in any book, but I cannot see why not. Also, if it can't be done, what will be a quickest method or passing from everything in one coordinate frame to another?

Thank you.
 
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Andromon said:
So here is my question: is there anyway to relate the scale factors (and everything else, from radius vector expression to operators expressoins) just using the Jacobian or derivates matrix?
Yes. The scale factor is the determinant of the Jacobian matrix, the matrix with the first partial derivatives of the components in one coordinate system with respect to the components in the other coordinate system.
 
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