Geodesics and Motion in an EM Field

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The discussion focuses on the challenges of calculating geodesics in an electromagnetic (EM) field, specifically regarding the partial derivatives in the equations. The original poster expresses difficulty in obtaining the correct terms, noting that they only achieved one A partial term. Upon further reflection, they identify a mistake related to the chain rule, realizing that the partial derivative of q A_b with respect to lambda is not zero and introduces an additional term. This correction leads to a more accurate formulation of the problem. The conversation emphasizes the importance of careful application of calculus in theoretical physics.
Woolyabyss
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Homework Statement
I've attached the problem statement as an image.
Relevant Equations
Euler Lagrange equations
I've also attached my attempt as a pdf file. My main issue seems to be I only get one A partial term. Any help would be appreciated.
 

Attachments

  • electro.png
    electro.png
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  • electro solution.pdf
    electro solution.pdf
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I've just realized my mistake. the partial of q A_b with respect to lambda isn't zero, you get an extra term from the chain rule and it works out nicely.
 

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