Consider a typical adult weighing 1650 lb and possessing a d

Consider a typical adult weighing 165.0 lb and possessing a density of 903.0 kg/m3. How low will the chamber need to drop in pressure at minimum to measure the person\\\'s density if the weight scale can only measure to the nearest 0.20 lb? (Assume air is an ideal gas and the chamber is maintained at standard temperature as the air is evacuated. The density of air at sea level is roughly 1.22 kg/m3.)

Solution

the change in pressure is calculated as follows:

     dp = p2 - p1 = [m1/m2][d2/d1]*p1 - p1

                         = [165 / 0.20][1.22 / 903]*1.013x10^5 - 1.013x10^5

                         = 1.161e+4 Pa