Electric Field of Two Point Charges on the x-axis

[Ryo124]

Two point charges, q1 = 4.0×10-6 C and q2 = -1.0×10-6 C, are located on the x-axis at x1 = -1.0 cm and x2 = 3.0 cm.

(a) Determine the electric field at the origin.

(b) Determine the x coordinate of a point on the positive x-axis where the electric field is zero; i.e., a test charge placed at this point would experience no force.

3. The Attempt at a Solution

I have no idea

 

[Ryo124]

OK, I solved part a) and found the electric field at the origin.

Can someone help me with part b), I really don't have a clue on how to solve this other than setting F = 0 (which may not be necessary anyway).

 

[Ryo124]

I am really interested in what this answer would be, as I have thought about it a lot. Could someone please guide me to the answer?