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calculating electrodynamic momentum of a dumbbell (consisting of two point charges) in longitudinal motion

I'm working through a paper on momentum in electrodynamics that requires the integration below and would greatly appreciate any help. I'm pretty sure it evaluates to $2/d$ but I can't quite figure ...
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What will happen when measuring unmeasurable object?

There is a set called Vitali Set which is not Lebesgue measurable. Analogously, there also exists a Vitali set $Y$ in $\mathbb R^3$ which is a subset of $[0,1]^3$ and $|Y\cap q|=1$ for all $q\in ...
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216 views

What is the definition of density as a function?

(Before I start, I don't know which tag is suitable for this post. Please retag my post if it bothers you.) Let's say there is a string on $[0,1]$ with a mass given by $m(x)$. ($m(x)$ means the mass ...