Integrating a Uniform Magnetic Field: Solving for ∫Bdl

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Mdhiggenz
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Homework Statement



Photo of a printed physics problem sheet, PHY2049 Challenge/Extra Credit Problem, with equations for a moving charged particle's magnetic field and Ampere's law, plus a diagram of a circular loop beside a moving charge labeled +q.


Handwritten notes on lined paper: a left-hand side labelled LHS with a line integral of E-dot-dl, a sketch of a point charge q with radius r and distance x, and a right-hand side flux integral of E-dot-dA leading to a double integral in r and phi with cos phi = x/r'.


I already worked out the right hand side. What is giving me problems is figuring out the left hand side, ∫Bdl

Since B is uniform, it can be removed from the integral leaving B∫dl

now I'm stuck.





Homework Equations





The Attempt at a Solution

 
Mdhiggenz said:
What is giving me problems is figuring out the left hand side, ∫Bdl

Since B is uniform, it can be removed from the integral leaving B∫dl

now I'm stuck.

∫dl is just the sum of all the elements of length around the circle of radius R. Your work up to this point looks good to me.