In: Physics
A charge
q1 = 2.72
a ) electric potential at point A due to charge q1 at distance d/3( = 0.61m ) is
V1 = k*q1/r = 9*10^9*2.72*10^{-6}/0.61 = 40.13*10^3 V
electric potential at point A due to charge q2 at distance 2d/3( = 1.22m ) is
V2 = k*q2/r = 9*10^9*(-5.57)*10^{-6}/1.22 = -41.09*10^3 V
net electric potential at point A between two charges is = -960 V
b) let x be the distace from Q1 to point A
and (d-x) be the distace from Q2 to point A
then V1 = 24.42*10^{3}/x and V2 = -50.13*10^{3}/(d-x)
for net electric potential to be zero
V1 + V2 = 0
on solving we get x = 0.4521 m
hence if point is placed at a distance of 0.4521m from Q1 the electric potential is zero