Question

two electric charges 12 microcoulomb and minus 6 microcoulomb are placed 20cm apart in air there will be a point P on the line joining the charges in outside the region between them at which the electric potential is zero the distance of P from -6 micro coulomb charge is​

Answer 1

Let distance of P from -6µC charge is x cm.

given, distance between 12µC and -6µC , r = 20cm.

so, distance of the point P from 12µC charge is (20 + x)cm

now, potential at P due to -6µC = K(-6µC)/(x cm)

and potential at point P due to 12µC = K(12µC)/(20 + x)cm

a/c to question, potential at point P due to system of charges = 0

or, potential due to -6µC + potential due to 12µC = 0

or, K(-6µC)/(x cm) + K(12µC)/(20 + x)cm = 0.

or, K(6µC)/(x cm) = K(12µC)/(20 + x)cm

or, 6/x = 12/(20 + x)

or, 20 + x = 2x

or, x = 20cm

hence, distance of P from -6µC charge is 20cm

Answer 2

Answer:

Qu a to k 27 t kl

r r t Vz 20cm