A stationary ring of radius a lies in the yz plane and has a uniform positive charge Q. A small particle that has mass m and a negative charge -q is located at the center of the ring.
a) Find the force on a particle as a function of x. [F(subx)=(blank)]
b) Show that if the particle is given a small displacement in the +x direction, it will perform simple harmonic motion.
c) What is the frequency of that motion?