Answer:
[tex]x=2L\pm \sqrt{\frac{(-2L)^2-4\times 1\times(-L^2)}{2\times 1} }[/tex]
Explanation:
Given:
Now the third charge must be placed on the line joining the two charges at a distance where the intensity of electric field is same for both the charges that point will not lie between the two charges because they are opposite in nature.
[tex]E_1=E_2[/tex]
[tex]\frac{1}{4\pi\epsilon_0} \times \frac{q_1}{x^2} =\frac{1}{4\pi\epsilon_0} \times \frac{q_2}{(L+x)^2}[/tex]
[tex]\frac{2.37}{x^2} =\frac{4.74}{L^2+x^2+2xL}[/tex]
[tex]2x^2=L^2+x^2+2xL[/tex]
[tex]x^2-2L.x-L^2=0[/tex]
[tex]x=2L\pm \sqrt{\frac{(-2L)^2-4\times 1\times(-L^2)}{2\times 1} }[/tex]