two point charges + 1n C and -4 nc are 1m apart in air . Find the positions along the line joining the two charges at which resultant potential is zero.

Explanation

`V= (1)/(4piepsilon_(n) ) (q)/(r )`
Position between the changes
`V_(1) + V_(2)= 0`
`(1)/(4piepsilon_(0)) (1xx10^(-9))/(X) +(-(1)/(4piepsilon_(0))(4xx10^(-9))/(1-x))=0`
`(1)/(4piepsilon_(0))(1xx10^(-9))/(x) = (1)/(4piepsilon_(0)) (4xx10^(-9))/(1-x)`
`4x=1-x`
`4x = x=1`
`5x=1`
`x= 0.2m`
position beyond the charges

`(1)/(4piepsilon_(0)) (1xx10^(-9))/(x) = (1)/(4piepsi_(0)) ( 4xx10^(-9))/( 1+ x)`
`4x=1+X`
`3X=1`
`X= 0.333 m`