The paper examines the effect of the Hall current in non-stationary hydromagnetic flow on an infinite plate in a constant plane magnetic field whose plane forms an angle $\theta$ with the normal to the plane of the plate. Analytical expressions are derived for the velocity field and for the components of the frictional shear stresses in contact with the plate, in the form of a time-order power. The case of accelerated plate motion is discussed in detail with an analysis of the effect of the Hall parameters $\omega\tau$, angle $\theta$ and magnetic field ($mt$) on the observed flow.