Answer:
-639288.89 N/C
Explanation:
x = 21-6 = 13.5 cm
[tex]x_1[/tex] = 6 cm
[tex]x_2[/tex] = 21 cm
[tex]q_1=q_2=-2\times 10^{-7}\ C[/tex]
k = Coulomb constant = [tex]8.99\times 10^{9}\ Nm^2/C^2[/tex]
The net electric field is given by
[tex]E_n=E_1+E_2\\\Rightarrow E_n=-\dfrac{k|q_1|}{(x-x_1)^2}\hat i-\dfrac{k|q_2|}{(x_2-x)^2}\hat i\\\Rightarrow E_n=-\dfrac{8.99\times 10^{9}\times 2\times 10^{-7}}{(0.135-0.06)^2}\hat i-\dfrac{8.99\times 10^{9}\times 2\times 10^{-7}}{(0.21-0.135)^2}\hat i\\\Rightarrow E_n=-639288.89\ N/C(\hat i)[/tex]
The net electric field is [tex]-639288.89\ N/C(\hat i)[/tex]
