Blood flows through a section of a horizontal artery that is partially blocked by a deposit along the artery wall. As a hemoglobin molecule moves from the narrow region into the wider region, its speed changes from v2 = 0.800 m/s to v1 = 0.422 m/s. What is the change in pressure, P1 - P2, that it experiences? The density of blood is 1060 kg/m3.

Question

Would I start by dividing the two values for v?

Answer 1

In a flow without friction the total pressure as sum of static and dynamic pressure is constant.
p1+(ρ•v1²/2) = p2+(ρ•v2²/2),
p1-p2 = (ρ/2)•( v1² -v2²)=
=(1060/2) •(0.422² - 0.8²) = ...

Answer 2

what units do you use for the answer?