Solution :-
a) The change in potential energy of the charge system isequal to
workdone by the charge system
                                ΔU
= W = -qEd
  Where
           E
= 240 i V/m
           q
= +13.0µC
           d
= 0.20i + 0.50j
    Therefore
  ΔU = - (13μC) * (240 i V/m)*(0.20i )
  = - 6.24 x 10-4
JÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â
b) The potential difference is
                 ΔV
= ΔU / q
                       =
- 6.9 x 10-4 J / 15μC
                       =
- 48 V
