Two point charges `-2nC` and `+8nC` are separated in air by a distance of 0.10m.Find the position of the neutral point along the line joining the 2 point charges.

Explanation

`q_(1)=-2nC,q_(3)=+8nC,d=0.10m`
`E_(1)-E_(2)=0` at `Q, E_(3)+E_(4)!=0` at P
`E_(1)=E_(2)` (for neutral point)

`(1/(4 p epsilon_(2)))((2xx10^(-9))/(x^(2)))=(1/(4 pi epsilon_(0)))((8xx10^(-9))/((0.10+x)^(2)))`
`[((0.1+x)^(2))/x]=2^(2)`
`0.1+x=2x`
`x=0.1m` to the left of A