12 J of work has to be done against an existing electric field to take a charge of 0.01 C from $A$ t

Question

12 J of work has to be done against an existing electric field to take a charge of 0.01 C from $A$ to $B$ without acceleration. How much is the potential difference $V_B-V_A$ ?

Professor PC Thomas Classes · Answer

$V_B-V_A=\frac{U_B-U_A}{q}$
$\begin{aligned} W_{e x t}+W_{e l} & =0 \ W_{e x t} & =-W_{e l}=\Delta U\end{aligned}$