i have been pondering something. this is it: if a fellow had a tube with a plunger in it, like a syringe but without an opening for a needle or such. say the plunger is at the bottom of the tube. If you start to pull/raise it, it is my understanding that the force required to lift it would be equal to the weight of the column of air in the atmosphere described by the area of the plunger's cross section. Would this mean then that after that force had been met that then the energy needed would plateau? Say you go to pick up a 50 lb weight, you strain until it is lifted but then it does not get any harder. Is this the same with vacuum? Another thing: I you are in space, since here are no forces on either side of the previously mentioned tube-and-plunger, would suction exist?