Having gone through the history of the development of magnetism, we may now
begin our quantitative analysis of magnetic fields and forces. The study of
magnetic fields is quite complicated, much more complicated than that of
electric fields, and requires more effort to fully
describe. The largest challenge regarding magnetic fields is the absence of
magnetic charge. With electric fields, we were able to describe the field
created in terms of a single charge, then generalize for a number of charges.
With magnetic field, there are multiple sources of fields, not a single
indivisible quantity, such as charge.
As such, we must begin
by defining the forces felt by moving particles in magnetic fields without
defining the source of the field. Don't worry in this section if you find the
situations a little hard to grasp conceptually. We are working with an
incomplete picture of magnetic fields, something that will be remedied in the
next SparkNote. After
defining forces felt by moving particles, we generalize our concepts for many
This SparkNote puts in place the first piece of the puzzle of magnetic fields. From
the definitions we here derive we will be able to move on to describe not
only the forces from magnetic fields, buy the sources of the fields.