The average velocity of blood flow in the aorta in a resting person is 20 cm/s. The radius of the aorta is 1.2 centimeter. At rest, the number of opened capillaries is about n = 12 x 109.They have on average a length l = .75 millimeter and a radius r =3 μm.
a. Determine the blood flow velocity in the capillaries?
b. Find what time does a red blood cell spend in a capillary on average?
c. Determine the total area of all the capillary walls? Compare this with the total surface area of all the red blood cells in the blood.