I push on a wall and the wall pushes me back (according to newton's third law), but what i don't understand is that no acceleration is produced hence is it not that i have not applied any force??? If i jump then i return to the ground (obviously) then doesn't the earth accelerate towards me? How much is that acceleration? How come nobody can tell if it has accelerated? I know these questions are dumb, but just trying to clear a few niggling doubts..!