Computing electric field divergence with Mathematica Manipulate

[mateomy]

I'm trying to make a little manipulate/interactive box that shows the vector divergence of the E-field coming from a sphere. I have no idea how to start as I'm really new to Mathematica. Does anyone have any pointers? I can't find anything particularly helpful on the Wolfram reference or Demonstrations site. Thanks.

 

[spamiam]

I'm trying to make a little manipulate/interactive box that shows the vector divergence of the E-field coming from a sphere. I have no idea how to start as I'm really new to Mathematica. Does anyone have any pointers? I can't find anything particularly helpful on the Wolfram reference or Demonstrations site. Thanks.

I'm no expert at Mathematica, but I've used StreamPlot and VectorPlot to create vector fields in two dimensions. I've never tried it in 3D, although there is a VectorPlot3D command. Anyway, I've attached the example I did.

 

[mateomy]

Thank you, very helpful.