1. The problem statement, all variables and given/known data Two positive charges +Q are affixed rigidly to the x axis one at x = -d and the other at x = +d. A third charge +q of mass mwhich is constrained to move only in the x axis is displaced from th eorigin by a small distance s << d and then released from rest. Show that q+ will execute simple harmonic motion and determine the oscillation period T. 2. Relevant equations Coulomb's Law F=kQ1Q2/r2 *possibly something else to relate this to SHM* 3. The attempt at a solution I found the force from coulomb's law, F= -4kQqs/d3 but i really don't know how to relate this to SHM so i can derive an equation for period.