Answer:
3N/C
Explanation:
Thinking process:
Let, electric field of 4N/C is in the positive x direction, that is + 4 NC
And the the resulting electric field on the x axis at x =2m
Therefore, based on the data above, the net charge must be in the positive direction. Thus, the magnitude is given by the equation:
[tex]q = \frac{Er^{2} }{k} \\ = \frac{4 (4)}{9*10^{4} } \\ = \frac{16}{9}NC[/tex]
Now considering that at x = + 4 NC, the net charge will be:
[tex]E_{net} = E_{0} + E_{q} \\ = 4 -(\frac{9*10^{} }{16}*\frac{16}{9} * 10^{-90})\\ = 3 (N/C)[/tex]