Problem #2. 1.28 g of a powder of particle density 2500 kg/m3 are charged into the cell of an apparatus for measurement of particle size and specific surface area by permeametry. The cylindrical cell...

Extracted text: Problem #2. 1.28 g of a powder of particle density 2500 kg/m3 are charged into the cell of an apparatus for measurement of particle size and specific surface area by permeametry. The cylindrical cell has a diameter of 1.14 cm and the powder forms a bed of depths 1 cm. Dry air of density 1.2 kg/m3 and viscosity 18.4 x 106 Pa-s flows at a rate of 36 cm³/min through the powder (in a direction parallel to the axis of the cylindrical cell) and producing a pressure difference of 100 mm of water across the bed. Determine the surface-volume mean diameter and the specific surface of the powder sample.