Originally Posted By: kallog
Hey, not that I know what that formula's all about but have you two both totally overlooked this really simple miscommunication?

- Paul says Ve is velocity
- Imaginggeek says Ve is zero

Just saying it back and forth to each other doesn't change the fact that you're obviously talking about different quantities!!!!

Actually, Paul and I agree on this - Ve is a velocity. Where paul is wrong is in how that velocity is calculated - it is the velocity ADDED to the air coming out of the tank, due to the acceleration of the gas caused by a divergent nozzle.

Paul stated the air was coming out of a tube - i.e. there is no divergence. As such Ve (keeping in mind, Ve is the added velocity, not the absolute velocity) will be zero.