Two point charges `+10nC` and `-10nC` are separated by a distance of 0.02m. Calculate the electric field intensity at a point P on the axis of the dipole at 0.01 from `+10nC`.

Explanation

We know that
`E_(A)=(1/(4 pi epsilon_(0)))(2pr)/((r^(2)-a^(2))^(2))Vm^(-1)`
i.e. `E_(A)=(9xx10^(9)xx2xx(0.02xx10xx10^(-9))(0.02))/([(2xx10^(-2))^(2)-(1xx10^(-2))^(2)]^(2))`
`E_(A)=(72xx10^(-3))/(10^(-8)(3))=24xx10^(5)Vm^(-1)`