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What is Poiseille's-Hagen law is related to and explain in detail?
In the small blood vessels, essentially all the blood is near the wall, so extremely rapidly flowing central stream of blood doesn&;t exist. By integrating the velocities of all the concentric rings of flowing blood and multiplying them by the areas of the rings one can derive the formula known as poiseuille&;s law.In the equation, the rate of blood flow is directly propoional to 4th power of the radius of vessel.Ref: Guyton and Hall, Textbook of medical physiology, 2nd South Asia Edition, page no. 233