This animation shows the graph of position versus time and velocity versus time for the red mass pushed by a 12N force on a frictionless horizontal surface.  The 2-kg red block is in contact with (and therefore pushes on) the green 1-kg block. When ready, fill in the values of the force below and check to see if you get the same plots.  Note that if you choose the wrong values, you may see the red block "move through" the green one.  Also, do not forget about the sign of the force vectors!