Science a GoGo's Home Page Forums General Discussion Sci Fi Forum Orion, Mission to Alpha Centauri

lets add up all the forces that apply.
as the air is escaping from the tank.

the ends of the tank

114.7 psi --->
114.7 psi <---

the ends of the pipe

14.7 psi --->
14.7 psi <---

the rear of the nozzle as the air enters the nozzle

114.7 psi --->
14.7 psi <---

the front of the nozzle as the air escapes the nozzle

114.7 psi --->
14.7 psi <---

action = reaction

net result of force to pipe 100 psi <---

nothing is gained inside the pipe , nothing is lost inside the pipe except the energy that was put into compressing the air , but the pipe moves.

I would wager that the exact amount of energy that is is held in the compressed air ( due to its compression ) inside the tank is the exact amount of energy that is applied for propulsion of the pipe.