The first Stokes problem is defined as one that describes the abrupt movement at constant speed of a flat plate in an incompressible Newtonian fluid $($transient Couette without pressure gradient in the direction of motion$).$ Consider a fluid at rest on a horizontal flat plate before movement. At the instant $t=0$ the plate begins to move at a constant velocity $U.$ Assume that the fluid has a kinematic viscosity v$.$ El induced flow in the fluid is only caused by viscous stresses. a$)$ Simplify the Navier$-$Stokes equations for this case. b$)$ Approach the mathematical model by means of the finite difference method. c$)$ Clear the ratio for the value of velocity at an arbitrary point of the fluid at time t$+1.$

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