Final answer:
The net force acting on a stationary charged particle suspended at the center is zero. When moving through a magnetic field, a charged particle experiences a perpendicular force, causing circular motion if the magnetic field is uniform.
Step-by-step explanation:
If a charged particle is suspended at the center and remains stationary, we can infer that the net force acting on the particle is zero. This is because, if the charged particle is not moving, there are no unbalanced forces causing it to accelerate in any given direction. The conditions in this scenario do not provide information on the direction of the net force should it be non-zero, as it only describes the particle being suspended and not moving. However, when a charged particle moves through a magnetic field, it experiences a force that is always perpendicular to its velocity. This results in the particle undergoing circular motion if the motion is perpendicular to a uniform magnetic field. This is due to the fact that the magnetic force provides the necessary centripetal force for circular motion. It's also important to note that the presence of other charges may influence the net force on the particle, as per Coulomb's Law.