2)
As pointed out in the Chapter 1, the field E is not just
an artefact but has a physical role It can  convey  energy
and momentum and is not established instantaneously
but takes finite time to propagate The concept of a field
was specially stressed by Faraday  and was incorporated
by Maxwell in his unification of electricity and magnetism In addition to depending on each point in space, it can
also vary with time, i