Well I can't argue with your logic because it's the same as my own, that is what I would have done. I will have to go and ask my lecturers about the notes. Thanks very much for your time and help.
Oliver
okay. I may have to talk with some of my lecturers then :D hopefully you can now see the images now though if you want to look at their full derivation. and I've also uploaded an image of Newtons cradle. I was thinking the three balls in the middle may act like the wall and the two particle...
The axial force F is the force on the duct/nozzle I believe, as a result of the fluid flowing through it. I've uploaded another image below. Your answer is what I thought also, but I'm fairly sure we are both wrong, or I just explained it badly to you :D, because this is what we have always been...
Is it similar to the Newton's cradle principle?
This is fluid mechanics/control volumes. There is fluid flowing through a duct and it's being analysed using a control volume surrounding the duct
For example in this question the atmospheric pressure is having an affect on the fluid within the...