The mechanical analog of an inductor is a mass. The voltage
across an inductor
corresponds to the force
used to
accelerate a mass
. The current
through in the inductor
corresponds to the velocity
of the mass. Thus,
Eq.(E.4) corresponds to Newton's second law for an ideal mass:
where
From the defining equation
for an inductor [Eq.(E.3)], we
see that the stored magnetic flux in an inductor is analogous to mass
times velocity, or momentum. In other words, magnetic flux may
be regarded as electric-charge momentum.