Two equal negative charges `-q` are fixed at points (0, a) and (0, -a). A positive charge Q is released from result at the point (2a, 0) on the X-axis. The charge Q will ………………

Options

A. move to the origin and remain at rest there
B. execute simple harmonic motion about the origin
C. move to infinity
D. execute osicllations but not simple harmonic motion

Answer

D

Explanation

Force exerted by charges `-q` at A and B, `F=(kQq)/(r^(2))`
Resultant is along the x-direction towards the origin `F^(2)=F^(2)+F^(2)+2F^(2)costheta=2F^(2)(1+costheta)`
`Fprop(1)/(r^(2))`
Q will oscillate but motion is not SHM