Divergence in spherical polar coordinates

The reason that confused me was Electric fields can have a non zero divergence. Is that because of the singularity at r=0?

The divergence is not 0, it's [itex]4 \pi \delta^{(3)}(\vec{x})[/itex]. It's not too tricky to prove with help of Green's first integral theorem applied to the whole space with a little sphere around the origin taken out and then taking its radius to 0.

This by definition is a singularity isn't it?

In physics it's often modelled thusly AAMOI:



I know not relevant but...

greek to me :)

meh a and b are just constants and F(X) is obviously the Function of X.

E(X) being the Energy of the system.

greek with a few constants and a function of x now =)

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