Question

Three charges -q₁, + q₂ and -q₃ are placed as shown in the figure. The x-component of the force on -q₁ is proportional to

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

$F_2=$ Force applied by $q_2$ on $-q_1$
$F_3=$ Force applied by $(-q_3)$ on $-q_1$
x-component of Net force on $-q_1$ is
$F_x=F_2+F_{3}sin\theta =K\frac{q_1{q}_2}{b^2}+K.\frac{q_1{q}_3}{a^2}sin\theta$

$\Rightarrow F_x=K[\frac{q_1{q}_2}{b^2}+\frac{q_1{q}_3}{a^2}sin\theta ]$

$\Rightarrow F_x=K.q_1[\frac{q_2}{b_2}+\frac{q_3}{a^2}sin\theta ]\Rightarrow F_x\propto (\frac{q_2}{b^2}+\frac{q_3}{a^2}sin\theta )$