Question

Three point charges are arranged along x-axis as follows: charge q1 = 3.0 µC is
at the origin, and charge q2 = - 5.00 µC is at x = 0.200 m. Charge q3 = -8.00 µC.
Where is q3 located if the net force on q1 is 7.00 N in the -x-direction?

Answer 1

A sketch of $q_3$ between $q_1$ and $q_2$ pushes the Force$(F)$ towards the left.

$F$ from point $3$ tends towards left.

$C=$ $(-5\times -8)\over (0.200-x)^2$

$F$ from point $1$ also tends towards the left.

$\therefore C=$ $(3.0\times 8)\over (x)^2$

$C=$ $40\over (0.04-x^2)$ $+$ $24\over x^2$ $=7.00$

$C=\mu^{3k}$