Unsteady hydromagnetic Couette flow of a viscous incompressible electrically conducting fluid in a rotating system
in the presence of a uniform transverse magnetic field is studied. The plates of the channel are considered porous and
fluid flow within the channel is induced due to the impulsive movement of the upper plate of the channel. General
solution of the governing equations is obtained which is valid for every value of time t. For small values of time t, the
solution of the governing equations is obtained by Laplace transform technique. The expression for the shear stress at
the stationary plate due to the primary and secondary flows is obtained in both the cases. It is found that the solution
obtained by Laplace transform technique converges more rapidly than the general solution when time t is very small.
Magnetic field retards the fluid flow in both the primary and secondary flow directions. Rotation retards primary flow
whereas it accelerates secondary flow. There exists incipient flow reversal near the stationary plate on increasing
rotation parameter K2. Suction accelerates primary flow whereas it retards secondary flow. Injection retards both the
primary and secondary flows
