Two equal negative charges -q are fixed at points (o,a) and (o,-a). A positive charge is released from rest at the point `(2a,0)` on the x-axis. What type of oscillations does the charge Q execute ?

Explanation

Let x be the small displacement of charge Q.
Now hy finding the net force on Q and then its acceleration .a..
`a = 2kQ q (x)/(m(x^2 + 1^2)^3//2)`
We can find that `a prop -x` not valid. Therefore charge Q will execute oscillations but not SHM.