i know we need to calculate the volume of the cylinder, this is spirometer test but how can we get FEV1 and FVC to get the pulmonary function %?

Question

spirometer test, cylinder tube diameter is 5cm in 1 diameter, 25 long and short term breathing for 15 min or less what will be the short term effect on the initially at rest breathing of a normal adult

Answer 1

There is no way to calculate the FEV1 or FVC In the preceding paragraph. Without a thorough explanation, it appears they are attempting to describe what occurs at varying resistances of respiration. This is principally related to the square of the inner diameter of the tube, Much less of the length.

Typically this would be connected to a ventilator which would calculate Minute ventilation, tidal volumes, inspiratory/expiratory pressures, etc. It would likely be more accurate to directly use your pneumotachometer, But obviously the smaller the tube the greater the workload and expected findings