For a particle of mass m, singly ionized with a charge e, accelerated by a field E over a distance l, aqcuires an energy given by:

where v is the velocity.

The mass spectrometer illustrates how an electric field can produce a force on charged particle and how a magnetic field can produce a force upon a moving, charged particle.

Try changing the parameters, and see how the path of the particle changes.
Notice that heavier particles takes longer to change direction, given that the strenght of the field is the same.
Similarly, for equal particles a stronger magnetic field will make the radius of the path smaller.

But remember; the particle always follows a circular path. This is because the magnetic force is the only force acting on it.