A uniformly charged thin ring has radius 15.0 cm and total charge +24.0 nC. An electron is

Question:

A uniformly charged thin ring has radius 15.0 cm and total charge +24.0 nC. An electron is placed on the ring's axis a distance 30.0 cm from the center of the ring and is constrained to stay on the axis of the ring. The electron is then released from rest.
(a) Describe the subsequent motion of the electron.
(b) Find the speed of the electron when it reaches the center of the ring.