Question

if two identical spheres having charge 16 μc and -8μc are kept at certain distance apart then the force is F they are touched and.again kept at the same distance, the force becomes

Answer 1

When they are touched then charge on them will be equally distributed.
 q= 4 μC on each sphere.
Therefore F' = k(4)2r2F 
= k×16×8r2F' 
= 1616×8F
 = F/8
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