From the Earth's bow shock observations and theoretical modeling it is
known that electrons are accelerated by a nearly perpendicular shock
wave. The theory of acceleration is well established for the case of a
plane shock wave. In this paper we revisit the role of a shock curvat
ure. We describe our model of a curved shock wave with zero thickness
in two and three dimensions (cylindrical and spherical) and compare th
e results of acceleration by plane and curved shock waves. We present
a method for the calculation of electron acceleration by a curved shoc
k wave of a general shape. We show that the acceleration by the spheri
cal shock can be reduced to the acceleration by the cylindrical shock,
but this is not true for a general shock (like the Earth's bow shock)
. We verified the approximation of a nearly perpendicular shock by a t
angent plane with variable magnetic field normal component. Even thoug
h the zero shock thickness is not very realistic for electron accelera
tion, it enables us to elaborate methods and test ideas that will be a
pplied in future work on the problem of nonzero shock thickness.