Lung compliance: C = ΔV/ΔP; If ΔV = 0.5 L and ΔP = 12 cmH2O, what is C in L/cmH2O?

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Lung compliance: C = ΔV/ΔP; If ΔV = 0.5 L and ΔP = 12 cmH2O, what is C in L/cmH2O?

Lung compliance is how much volume changes per unit pressure change, expressed as C = ΔV/ΔP. With a volume change of 0.5 L and a pressure change of 12 cmH2O, the calculation is C = 0.5 L ÷ 12 cmH2O ≈ 0.0417 L/cmH2O, which rounds to 0.042 L/cmH2O. This is the value that matches the given changes in volume and pressure. If you tried the other options, they would imply either far smaller or far larger volume changes for the same pressure shift (for example, 0.005 would correspond to about 0.06 L change, 0.12 would imply about 1.44 L, and 0.50 would imply about 6 L), none of which fit the provided ΔV and ΔP.

Lung compliance is how much volume changes per unit pressure change, expressed as C = ΔV/ΔP. With a volume change of 0.5 L and a pressure change of 12 cmH2O, the calculation is C = 0.5 L ÷ 12 cmH2O ≈ 0.0417 L/cmH2O, which rounds to 0.042 L/cmH2O. This is the value that matches the given changes in volume and pressure.

If you tried the other options, they would imply either far smaller or far larger volume changes for the same pressure shift (for example, 0.005 would correspond to about 0.06 L change, 0.12 would imply about 1.44 L, and 0.50 would imply about 6 L), none of which fit the provided ΔV and ΔP.

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