The flow of blood in a blood vessel is faster toward the center of the vessel and slower toward the
outside. The speed of the blood is given by V =p
4Lv (R2–r2), where R is the radius of the blood
vessel, r is the distance of the flowing blood from the center of the blood vessel, and p, v, and L are
physical constants related to the pressure and viscosity of the blood and the length of the blood
vessel. If R is constant, we can think of V as a function of r: V(r) =p
4Lv (R2–r2). The total blood
flow Q is given by Q(R) =
R
0
2rV(r) dr . Find Q for a blood vessel of radius R =0.4 mm.