Sol. E = 2 N/C in x-direction
(a) Potential aat the origin is O. dV = – E base x dx – E base y dy – E base z dz
⇒ V – 0 = – 2x ⇒ V = – 2x
(b) (25 – 0) = – 2x ⇒ x = – 12.5 m
(c) If potential at origin is 100 v, v – 100 = – 2x ⇒ V = – 2x + 100 = 100 – 2x
(d) Potential at ∞ IS 0, V – V’ = – 2x ⇒ V’ = V + 2x = 0 + 2∞ ⇒ V’ = ∞
Potential at origin is ∞. No, it is not practical to take potential at ∞ to be zero.