Required information A 0.12 -mm-dlameter dust particle whose density is 2.1g/cm3 is observed to be suspended in the air at 1 atm and 25C at a fixed point. Assume Stokes law to be applicable. The density of dust is given to be s=2.1g/cm3=2100kg/m3. The density and dynamic viscosity of air at 1 atm and 25C are 1.184kg/m3 and =1849105kg/m.s. Determine the updraf velocity of air motion at that location. The updraft velocity of air motion is m/s