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Boyle’s Law


Boyle’s Law
Changes in intrapulmonary pressure occur as a result of changes in lung volume. This follows from Boyle’s law, which states that the pressure of a given quantity of gas is inversely proportional to its volume. An increase in lung volume during inspiration decreases intrapulmonary pressure to subatmospheric levels; air therefore goes in. A decrease in lung volume, conversely, raises the intrapul- monary pressure above that of the atmosphere, expelling air from the lungs. These changes in lung volume occur as a consequence of changes in thoracic volume,

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