Which of the following is true about the relationship between radius and flow when ΔP is constant?

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Multiple Choice

Which of the following is true about the relationship between radius and flow when ΔP is constant?

With a fixed driving pressure, the rate of flow through a tube scales with the radius to the fourth power. This comes from Poiseuille’s law: Q = (π ΔP r^4)/(8 μ L). If ΔP, μ, and L are constant, increasing the radius causes a large increase in flow because of the r^4 relationship. So when the radius increases while ΔP stays the same, the flow increases. The other ideas either describe a different condition (changing ΔP) or oppose the direct radius-to-flow effect, or describe a reverse implication that, under the same constant ΔP assumption, still aligns with the same underlying relationship.

With a fixed driving pressure, the rate of flow through a tube scales with the radius to the fourth power. This comes from Poiseuille’s law: Q = (π ΔP r^4)/(8 μ L). If ΔP, μ, and L are constant, increasing the radius causes a large increase in flow because of the r^4 relationship. So when the radius increases while ΔP stays the same, the flow increases. The other ideas either describe a different condition (changing ΔP) or oppose the direct radius-to-flow effect, or describe a reverse implication that, under the same constant ΔP assumption, still aligns with the same underlying relationship.

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