2.7 Calculate the total equivalent length of 1-in. wrought iron pipe that would produce a pressure drop of 70 kPa due to fluid friction, for a fluid flowing at a rate of 0.05 kg/sec, a viscosity of 2 cP, and density of 1000 kg/m³.

A Pitot-static probe was used to measure the velocity distribution in a water tunnel. The two pressure lines from the probe were connected to a U-tube manometer which uses a liquid of specific gravity 1.7. The maximum velocity expected in the water tunnel was 2.3 m/s. Your job was to select an appropriate U-tube from a manufacturer which supplies manometers of different heights. The cost increases significantly with manometer height. Which of these should you purchase?