The rotating flow of a third-grade fluid on an oscillating porous plate in
the presence of a transverse magnetic field is considered. An analytic solu
tion of the governing nonlinear boundary layer equation is obtained. Expres
sions for the velocity profile are established. It is found that an externa
l magnetic Field has the same effect on the flow as the material parameters
of the fluid. Further the symmetric and asymmetric nature of the solutions
is discussed.