$OA=\left|\vec{r}_{1}\right|=\sqrt{(\sqrt{2})^{2}+(\sqrt{2})^{2}}=\sqrt{4}=2$ units.
The distance of point $B(2,0)$ from the origin,
$O B=|\overrightarrow{r_{2}}|=\sqrt{(2)^{2}+(0)^{2}}=2$ units.
Now, potential at $A, V_{A}=\frac{1}{4 \pi \epsilon_{0}} \cdot \frac{Q}{(O A)}$
Potential at $B, V_{B}=\frac{1}{4 \pi \epsilon_{0}} \cdot \frac{Q}{(O B)}$
$\therefore $ Potential difference between the points $A$ and $B$ is zero.


Reason : In a hollow spherical shield, the electric field inside it is zero at every point.

Statement $1$ : It is not possible to make a sphere of capacity $1$ farad using a conducting material.
Statement $2$ : It is possible for earth as its radius is $6.4\times10^6\, m$

