In this paper we perform an asymptotic study of the Maxwell equations
with respect to the small parameter epsilon = upsilon/c where upsilon
is the characteristic velocity associated with the physical problem an
d c is the speed of light. This enables us to derive the quasistatic a
nd Darwin models as respectively first and second order approximations
of the Maxwell equations. Moreover, an interpretation of the obtained
variational formulations gives us the appropriate boundary conditions
for these models.