[Given: In SI units $\frac{1}{4 \pi \epsilon_0}=9 \times 10^9, \ln 2=0.7$. Ignore the area pierced by the wire.]
$dV =-\overrightarrow{ E } \cdot \overrightarrow{ dx }$
$\int_{T_{ r }}^{ V _{ R }} dV =-\int_{0.5}^2 \frac{2 k \lambda}{ x } dx$
$V _{ R }- V _{ P }=-2 k \lambda \ln \frac{2}{0.5}$
$=-2 \times 9 \times 10^9 \times 3 \times 10^{-9} \times 2 \times 0.7=-126$
due to sphere
$v_R-v_P=\frac{k Q}{2}-\frac{k Q}{1}=-\frac{k Q}{2}=\frac{-9 \times 10^9 \times 10 \times 10^{-9}}{2}$
$=-45 V$
$v_R-v_P=-126-45=-171 V$
$v_p-v_R=171 V$

Assertion $(A)$ and the other is labelled as Reason$(R)$
$Assertion$ $(A)$ : Work done by electric field on moving a positive charge on an equipotential surface is always zero.
$Reason$ $(R)$ : Electric lines of forces are always perpendicular to equipotential surfaces.
In the light of the above statements, choose the most appropriate answer from the options given below
