Figure $1$ below shows three$-$point charges, $q_1=+5\mathrm{.}0C,q_2=-4C$ and $q_3=+4\mathrm{.}0C$ located in the $x-y$ plane.

Figure $1$

i$.$ Draw the directions of the electrostatic forces on charge $q_3$ due to the charges $q_1$ and $q_2$

ii$.$ Determine the magnitude and direction of the net electrostatic force on the charge $q_3.$

Ans: $F=1\mathrm{.}386N,=32\mathrm{.}81$