Tiêu đề HPGE 13 Solutions.pdf ✅

13 Hydraulics: Fluid Properties Solutions SITUATION 1. A cylindrical tank 80 cm in diameter and 90 cm high is filled with a certain liquid. The tank and the liquid weighed 420 kg and the weight of the empty tank is 40 kg. Determine the following: ▣ 1. Mass density [SOLUTION] ρ = m V ρ = 420 kg − 40 kg π 4 (0.8 m) 2(0.9 m) ρ = 840 kg/m3 ▣ 2. Specific volume [SOLUTION] ν = 1 ρ ν = 1 840 kg m3 ν = 0.0019 m3/kg ▣ 3. Specific gravity [SOLUTION] Gs = ρ ρw Gs = 840 kg m3 1000 kg m3 Gs = 0.84 ▣ 4. Specific weight [SOLUTION] γ = ρg γ = (840 kg m3 ) (9.81 m s 2 )

▣ 9. A glass capillary tube, 2 mm in diameter, is placed on top of a mercury layer. Calculate the height of the capillary depression for mercury. The surface tension of mercury is 0.514 N/m and its angle of contact with the glass is 130°. [SOLUTION] h = 4σ cos θ γd h = 4 (0.514 N m ) cos 130° (13.6 × 9.81 kN m3 ) (0.002 m) h = −4.95 mm ▣ 10. Nitrogen gas at 30°C is under a pressure of 560 kPa. Assume a gas constant of 296.8 J/kgK. Calculate its specific volume. [SOLUTION] PV = mRT V m = ν = RT P ν = (296.8 J kg K ) (30° + 273.15°) 560 kPa + 101.325 kPa ν = 0.136 m3 kg