R sub 0 - normal radius
P sub 0 - normal pressure
R and P are the constricted values.
Use Poiseuille's Law:
F(flux- rate of blood past a given point) = (1/8) (pi PR^4/nl)
to show that P and R are related by the equation:
(P/Po) = (Ro/R)^4
note: Deduce that if the radius of an artery is reduced to 3/4 of it's former value, then the pressure is more than tripled.
I don't even know where to begin with this problem. Like, I can't even get started. What should I do? Help please!