When considering the pressure in the sheet very far away from the impact zone the argument is “the streamlines are parallel, therefore it’s atmospheric pressure”. This brings a few questions:
1) in a moving fluid, is the pressure exerted perpendicular to the streamlines not greater than on surfaces parallel?
2) Why is the pressure atmospheric?
3)What is the pressure term in Bernoulli for a moving fluid? Is it the pressure in the direction of motion, or the pressure being exerted in it by the surroundings? (This is obviously gonna be easier to answer eight rh help of 1).
4) why is the pressure very far away from the point of impact the same as the initial pressure (and hence the velocity the same)?