Thanks all for explanation! That was the part that I did not understand well despite the fact that I did research (probably not good enough). Thanks again, now I know what I am doing and that my physics works fine...
Happy xmas!
So there it is me trying to program some simple physics for flying ball. I have done some research and generally I was always understanding physics very well. But what is happening in my application is not understandable for me, even tho I have checked everything twice and I think everything...