
charge on $\mathrm{A}$ after connection $=\frac{7+1}{2}=4\, \mu \mathrm{C}$
Charge flow from $A$ to $B=7\, \mu C-4\, \mu C$
$=3\, \mu \mathrm{C}$

$STATEMENT-2$ The electrical potential of a sphere of radius $R$ with charge $\mathrm{Q}$ uniformly distributed on the surface is given by $\frac{\mathrm{Q}}{4 \pi \varepsilon_0 R}$.
