The variation in energy and thickness of a domain wall under the actio
n of an applied magnetic held is investigated using a two-dimensional
micromagnetic model, where it is assumed that the wall is pinned by in
clusions. It is shown that there is an increase in wail energy due to
the curvature produced in the wall, but that the change in this energy
is small. It is also shown that although there ism appreciable variat
ion in the thickness of the domain wall at the pinning points there is
no change in thickness at its midpoint with increasing magnetic field
. The curvature of the wall was found to depend on the pinning strengt
h of the inclusions.