Question 13 on the morning of the first day of 2011

The answer is C; there’s no need to discuss it further. According to the principles of statics, in flowing fluids, due to resistance losses, equipotential surfaces are not isobaric surfaces

President H, the question is about circulation, not flow~ All 4 options refer to stationary fluids. I think the answer is D – within the same fluid, at the same height, the pressure should be the same. What do you think?

I really don’t understand what the concept of circulation is. Is it connected? At first glance, it’s clearly statics – so how could there be a flowing system? Isn’t circulation just a dynamic term?

The exact words are in the book! It’s such a simple question; even with analysis one can get the answer right. Hurry up and work hard!

13. Based on the fundamental equations of hydrostatics, which of the following statements is incorrect? D A. Within a stationary fluid of the same type, the static pressure of the fluid at the same horizontal level is equal (correct; this relates to the concept of isobaric surfaces). B. Within a stationary fluid of the same type, surfaces with equal pressure must be at the same horizontal level (correct; since the pressure is equal, such a fluid must be at the same horizontal level). C. Within a stationary or flowing fluid of the same type, the static pressure of the fluid at the same horizontal level is equal (correct; this is also related to the concept of isobaric surfaces). D. Within a stationary or flowing fluid of the same type, surfaces with equal pressure are not necessarily at the same horizontal level (incorrect; they must be at the same horizontal level)

P=ρgh. The pressure at a certain point in a liquid depends on its density and depth; for the same type of liquid, the greater the depth, the higher the pressure