Hall effects on the unsteady hydromagnetic flow of a viscous incompressible electrically conducting fluid bounded by an infinite flat porous plate in the presence of a uniform transverse magnetic field has been analyzed. Initially ( ) the fluid at infinity moves with uniform velocity . At time , the plate suddenly moves with uniform velocity in the direction of the flow. The velocity field and the shear stress components at the plate are found exactly by using the Laplace transform technique. The solutions are also obtained for small as well as large times. It is observed that the primary velocity decreases whereas the secondary velocity increases with an increase in Hall parameter. The suction parameter is found to accelerate the primary velocity and it has a retarding influence on the secondary velocity. It is also found that the shear stress components decrease with an increase in time.

Hydromagnetic Hall currents inertial oscillations and porous plate