lew (04/19/83)
Rich Pavelle's description of the demonstration with the air moving through a heated glass tube would appear to be a model of a ramjet. As described however, I don't think it will work (move forward). If the sides of the glass tube are straight, the only force on them is the drag force of the moving air. As long as the air moves to the right it will drag the tube with it. To work as a jet there has to be a constricted opening to form an expansion chamber behind it. The heated air then pushes on the front wall of the chamber, driving the tube into the oncoming air. Lew Mammel, Jr. ihuxr!lew