A fan is to be selected to ventilate a bathroom whose dimensions are 19 m x 3.34 m x 4.7 m. The air velocity is not to exceed 16.5 m/s to minimize vibration and noise. The combined efficiency of the fan–motor unit to be used can be taken to be 50 percent. The fan replaces the entire volume of air in 10 min. The air density is 1.25 kg/m3 and disregard the effect of the kinetic energy correction factors.