141k views
0 votes
Flow through a coronary artery with a radius of 1um is 4um/sec during a recent bout of exercise. Assuming a constant pressure difference and a change in the radius by half, how would flow compare in that same coronary artery while this individual is resting?

1) Flow would be less, specifically 1 um/sec
2) Flow would be equal at 4 um/sec
3) Flow would be more at 16 um/sec
4) Flow would be less, specifically 1/4 um/sec
5) Flow would be more at 64 um/sec

1 Answer

6 votes

Final answer:

Flow through a coronary artery will be significantly less, specifically 1/4 um/sec, when the radius is reduced by half according to Poiseuille's Law.

Step-by-step explanation:

When considering how a change in radius affects the flow through a coronary artery, we can refer to Poiseuille's Law, which states that flow rate is proportional to the fourth power of the radius (r^4) when all other factors remain constant. The flow through the artery is initially 4µm/sec with a radius of 1µm. If the radius is halved, the new radius would be 0.5µm. The new flow rate would be proportional to (0.5µm)4 compared to (1µm)4. Since (0.5)4 is 1/16, the new flow rate would be 4µm/sec divided by 16, giving us a flow rate of 0.25µm/sec or specifically, 1/4 um/sec. Therefore, the flow would be significantly less when the individual is resting and the artery's radius is reduced by half.

User Yastanub
by
7.4k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.