When we make a gaschamber smaller, the kinetic energy increases <--> temperature increases <--> pressuere increases. Does this always happen? Isn't it possible to make a gaschamber smaller without applying work to the gas? Look at this: http://galileo.phys.virginia.edu/classes/109N/more_stuff/Applets/Piston/jarapplet.html [Broken] If the pistonhead is not moving during collison with the atom, the velocity of the atom doesnt change. Is it theoretically possible to make a gaschamber smaller, without any increase in kinetic energy, which means same pressure and temprature, but in a smaller volume?