(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

This problem involves an electric monopole placed at the origin and a magnetic monopole placed a distance D away, say arbitrarily, along the z-axis.

I need to compute the angular momentum of the EM fieds:

[itex]\vec{J_{field}} = \frac{1}{4\pi c}\int{d\tau \vec{r} \times (\vec{E}\times \vec{B})}[/itex]

The integral is over all space. After trudging along, I am left with the following integral:

[itex]\int_0^\infty{\frac{r dr}{[r^2 +D^2 -2Dru]^{3/2}}}[/itex]

If I can solve this last integral, I am home free.

2. Relevant equations

All terms in the integral, other than r, are constants with respect to r.

3. The attempt at a solution

I tried using integration by parts but was not able to get anywhere. "u" substitution taking the argument of the cube root in the denominator as "u" doesn't seem productive, either.

Unless my above two attempts were done wrong, I must say I am out of ideas.

Can anyone suggest anything?

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# Homework Help: Solving the Integral present in Dirac's quantization of charge problem

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