A positive charge `+q_(1)` is located to the left of a negative charge `-q_(2)` On a line passing through the two charges, there are two places where the total potential is zero. The reference is assumed to be at infinity The first place is between the charges and is 4.00 cm to the left of the negative charge. The second place is 7.00cm to the right of the negative charge if `q_(2)=-12muC` , what is the value of charge `q_(1) in muC`

Answer

`0044`

Explanation

`q_(1)/(x-4)-q_(2)/4=0 q_(1)/(x+7)-q_(2)/7=0`
`q_(1)/q_(2)=(x-4)/4 q_(1)/q_(2)=(x+7)/7`
`(x-4)/4=(x+7)/7`
`7x-28=4x+28`
`3x=56`
`x=56/3`
`q_(1)/q_(2)=(56/3+7)/7=11/3`
`|q_(2)|=+12 muc`
`Rightarrow q_(1)=12xx11/3=44muc`