posted by Josh .
There are two positive charges (+4C on the left and +6C on the right) that are both separated by an arbitrary distance. In order not to experience any net electric force where would you place the third charge.
I say to the left of the +4C charge am i right?
The third charge should be placed between the +4C and +6C charges so that the forces cancel out. That will NOT be to the left of the 4C charge.
If x1 and x2 are the distances to the +4 and +6 charges,
4/x1^2 = 6/x2^2
(x2/x1)^2 = 3/2
x2/x1 = 1.225
x1/(x1 + x2) = 1/2.225 = 0.449