Question

The aorta in an average adult has a cross-sectional area of 2.0 cm^2. Calculate the flow rate of blood of 1.0 g/cm^3 in the aorta if the flow speed is 43 cm/s.
Answer in units of g/s.
(I did this part and the correct answer is 86)

Assume that the aorta branches to form a large number of capillaries with a combined cross-sectional area of 2.9 × 10^3
cm^2. What is the flow speed in the capillaries?
Answer in units of cm/s.

Answer 1

As we know that flow rate will always remains the same

so here the flow rate from aorta = flow rate through large capillaries

so here we will have

flow rate through Aorta = $86 cm^3/s$

now we can also say that flow rate through capillaries is given by

$Q = Area\times speed$

as we know that

$Area = 2.9 \times 10^3 cm^2$

now from above formula

$2.9 \times 10^3 (v) = 86 cm^3/s$

$v = 0.0296 cm/s$

so the speed will be 0.0296 cm/s through capillaries