a distance which is a vector ??

[transgalactic]

https://i31.tinypic.com/2j4bp07.jpg

i have two sphere which are separated from their centers by d

when d is much smaller then their radii

so those spheres are not separated
but they are colided

i cant imagine the system
??

 

[maxmcp]

https://i31.tinypic.com/2j4bp07.jpg

i have two sphere which are separated from their centers by d

when d is much smaller then their radii

so those spheres are not separated
but they are colided

i cant imagine the system
??

Hi, sorry if this is too late. Is it possibly a typo, and d>>r0, in which case you can treat the spheres as point charges when considering the field between them. If they are collided, ie as the question says d<<r0, then treat it was one sphere I suppose. Using gauss' law the field outside the spheres (which will appear as a single sphere as their centres are practically the same) will be zero as there will be zero net enclosed charge.