A point charge `q_1 = + 2muC` is placed at the origin of coordinates. A second charge, `q_2 = - 3muC`, is placed on the x-axis at `x = 100cm`. At what point (or points) on the x-axis will the absolute potential be zero?

Answer

A, B, C, D

Explanation

`(kq_1)/r_1=(k|q_2|)/r_2`
`:. r_1/r_2=q_1/(|q_2|)=2/3`
where `r_1=` distance from `q_1` and
`r_2=` distance from `q_2`

First pont is at `x=40cm` where `r_1/r_2=2/3`

`x=-200 cm x=0`
Second point is at `x=-200cm` where `r_1/r_2=2/3`.