Question

Two equal negative charges – q are fixed at points (0,-a) and (0,a) on y-axis. A positive charge Q is released from rest at the point (2a, 0) on the x-axis. The charge Q will 

(A) Execute simple harmonic motion about the origin 

(B) Move to the origin and remain at rest 

(C) Move to infinity 

(D) Execute oscillatory but not simple harmonic motion

Answer 1

Correct option (D) Execute oscillatory but not simple harmonic motion  

Explanation:

Motion is simple harmonic only if Q is released from a point not very far from the origin on x-axis. Otherwise motion is periodic but not simple harmonic.