TEST 16 1. What is the equivalent head of a fluid that has a velocity of 18 m/s? A. 16.51 m B. 13.56 m C. 18.34 cm D. 11.41 cm 2. The length of pipe is 168 meters. If the pressure drop is 50 kPa for every 30 m, what is the total pressure drop? A. 240 kPa B. 260 kPa C. 280 kPa D. 220 kPa 3. Find the volume flow rate of water in L/s if the power developed under a head of 320 m is 10,500 kW and the hydraulic efficiency is 85%. A. 3,953 B. 3,293 C. 3,271 D. 3,935 4. Water flows in a pipe with a velocity of 10 m/s. Determine the velocity head of the water. A. 6.8 m B. 5.1 m C. 1.5 m D. 8.6 m 5. A cylindrical pipe with water flowing downward at 0.02 m 3 /s having top diameter of 0.08, bottom diameter of 0.04 m and height of 1.5 m. Find the pressure between the pipes. 94 kPa A. B. 124 kPa C. 104 kPa D. 134 kPa 6. The weight of the balloon and the gas it contains is 11.12 M. It the balloon displaced 1132 m 3 of air and weight of 1 m 3 of air is 12.3 N, what is the acceleration with which the balloon begins to rise? A. 2.47 m/s 2 B. 2.0 m/s 2 C. 3.76 m/s 3 D. 3.24 m/s 2 7. During a heavy rain, a 3 m x 4.6 m room is flooded to a depth of 15 cm. To remove the water (µ = 1.0 x 10-3 Pa.․), a pump is used that does the job in two hours. The water flows through a horizontal pipe of radius 0.64 cm and length of 6.7 m. Compute the gage pressure produced by the pump. A. 2.923 kPa B. 2.785 kPa C. 1.176 kPa D. 1.254 kPa 8. If the velocity of the flow in a 75-mm diameter fire hose is 25 cm/s, what is the power available in a 30-mm diameter jet issuing from a nozzle attached at the end of the pipe? A. 1.34 W B. 3.24 W C. 1.25 W D. 2.34 W 9. A 70.874 Us (150 ft 3/min.) of water is flowing in a round pipe such that the flow remains laminar. Considering that the critical Reynold's number to 2000, what is the diameter of the pipe necessary to ensure laminar flow? (Note: kinematic viscosity of water is 4.75 x 10-5 ft2/s) A. 33.50 ft. B. 41.70 ft C. 12.50 ft D. 37.50 ft 10. Water is flowing in a pipe of varying cross-sectional area, and at all points, the water completely fills the pipe. The cross-sectional area at point 1 is 0.080 m 2, and the velocity is 3.5 m/s. Compute the fluid's velocity at point 2 where the cross-sectional area is 0.060 m2. A. 4.67 m/s B. 2:57 m/s C. 5.22 m/s D. 3.25 m/s 11. A sealed tank containing seawater to a height of 12-m also contains air above the water at gage pressure of 5 -atm. Water flows out from the bottom through a small hole. Calculate the efflux speed of the water. Note: ρSW 1.03 x 103 kg/m 3. A. 34.92 m/s B. 45.24 m/s C. 20.45 m/s D. 35.45 m/s 12. A cylindrical bucket, open at the top, 0.200 m high and 0.100 m in diameter. A circular hole with cross-section area 1.0 cm 2 is cut in the center of the bottom of the bucket. Water flows into the bucket from a tube above it at the rate of 1.30 x 10-4 m 3/s. How high will the water in the bucket rise? =
A. 8.62 cm B. 4.67 cm C. 2.52 cm D. 1.25 cm 13. Modern airplane design calls for a lift due to the net force of the moving air on the wing of about 2000 N/m 2 of wing area. Assume that air density (density = 1.2 kg/m3) flows past the wing of an aircraft with streamline flow. If the speed of flow put the lower wing surface is 140-m/s, what is the required speed over the upper surface to give a lift of 2000 N/m2? A. 151 m/s B. 170 m/s C. 172 m/s D. 140 m/s 14. Water leaves a faucet with a downward velocity of 3 m/s. As the water falls below the faucet, it accelerates with acceleration g. The cross sectional area of the water stream leaving the faucet is 1.0 cm2. What is the cross-sectional area of the stream 0.50 m below the faucet? A. 0.96 cm2 B. 0.45 cm2 C. 0.69 cm2 D. 0.25 cm2 15. A hose shoots water straight up a distance of 2.5 m. The end opening on the hose has an area of 0.75 m 2. How much water comes out in min? A. 13.5 liters B. 41.5 liters C. 31.5 liters D. 130.5 liters 16. What is the force acting on one side of the tank moving upward with an acceleration of 4.7 m/s when it is filled with oil whose specific gravity is 0.752 and a height of 1.3 m for the bottom of the tank? A. 11.986 kN B. 14.572 kN C. 15.723 kN 17. The conical reducing sections connects an existent 10.16 cm diameter pipeline with a new 5.08 cm diameter line. At 689.30 kPa static pressure under no-flow conditions, what is the tensile force is exerted on the connectors at joint A assuming no end restraint from the pipe.
A. 4.91 kN B. 5.12 kN C. 3.23 kN D. 4.19 kN 18. An oil flowing at the rate of 0.001 m 3/s through an 8 cm diameter pipe has a kinematic viscosity of 2 x 10 -5 M2 /s and a specific gravity of 0.85. What is the centerline velocity? A. 0.398 m/s B. 0.678 m/s C. 0.235 m/s D. 0.547 m/s 19. Water at 20°C is flowing in a pipe of radius 1.0 cm. The viscosity of water at 20°C is 1.005 centipoise. If the flow speed at the center is 0.200 m/s and the flow is laminar, find the pressure drop due to viscosity along a 5 m section pipe. A. 20.4 Pa B. 40.2 Pa C. 13.4 Pa D. 45.8 Pa 20. A small block of wood of density 0.4 x 10 3 kg/m 3 is submerged in water at a depth of 2.9 m. Find the acceleration of the block toward the surface when the block is released in a water whose viscosity is to be negligible. A. 12.7 m/s2 B. 11.4 m/s2 C. 14.7 m/s2 D. 10.8 m/s2 21. A submarine is 100-m long. The shape of its hull is roughly cylindrical with a diameter of 15-m. When it is submerged, it cruises at a speed of about 40-knots or approximately 20 m/s. Compute the Reynolds number, if the viscosity is 1.0 x 10 -3 Pa.s. A. 6 x 108 B. 4 x 10 8 C. 3 x 108 D. 5 x 108 22. A hose shoots water straight up for a distance of 2.5 m. The end opening on the hose has an area of 0.75 cm 2. How much water come out in 1 hour? A. 1.89 m3 B. 1.67 m 3
C. 0.78 m 3 D. 2 56 m 3 23. The jet discharges water at the rate of 0.10 m 3 /s and at a speed of 18 m/s to stationary plate. Determine the force on the plate. A. 2800 N B. 2000 N C. 1800 N D. 2500 N 24. A 150-mm diameter pipe carries 81.3-L/s of water. The pipe branches into two pipes one is 50-mm in diameter and the other is 75-mm. What is the velocity in 75-mm pipe if the velocity of the flow in the 50-mm pipe is 10-m/s? A. 13.96 m/s B. 15.67 m/s C. 17.25 m/s D. 19.43 m/s 25. A gas flows through a square conduit, at the entrance the conduit sides are 10 cm, the velocity is 7.55 m/s, and the gas mass density is 1.09 kg/m 3. At the exit, the conduit sides are 25 cm, and the velocity of the flow is 2.02 m/s. Find the density of the gas at the exit section considering that the gas is compressible. A. 0.6598 kg/m3 B. 0.6851 kg/m3 C. 0.6518 kg/m3 D. 0.6185 kg/m3 26. What is the expected head loss per mile of a closed circular pipe with 17 in. inside diameter friction factor of 0.03 when 3300 gal/min of water flow under pressure? A. 27.7 ft B. 29.7 ft C. 35.7 ft D. 37.7 ft 27. A pipe has a diameter of 4 in. at section XX a diameter of 2 in. at section YY. An ideal fluid flow, the velocity is given as 2 ft/s at section XX. Determine the flow velocity at section YY. A. 4 ft/s B. 8 ft/s C. 5 ft/s D. 2.5 ft/s 28. What is the hydraulic radius of a semi-circular channel of radius 8 ft? A. 3 ft B. 2 ft C. 4 ft D. 1.5 ft 29. A sphere is falling in air with Reynold's number of 2 x 10 6. What is its velocity considering that the sphere's radius is 1 ft. Note: Pair = 0.00234 slug/ft 3, µair = 3.8 x 10 -7 lbf -s / ft. A. 234.1 ft/s B. 126.2 ft/s C. 123.7 ft/s D. 162.4 ft/s 30. EE Board September 2002 Find the speed of sound in 32°F water, if the compressibility is 3.4 x10 -6 psi? A. 4674 ft/s B. 4584 ft/s C. 4764 ft/s D. 4854 ft/s 31. A pipe of internal diameter 6 units carries water with a depth of 2 units under in influence of gravity. Calculate the Hydraulic radius. A. 1.12 B. 2.12 C. 3.12 D. 3.21 32. An open channel whose above length is 7-units and length below is 5 units. Compute the hydraulic radius if the water flowing is 3 units deep. A. 1.59 B. 1.21 C. 2.05 D. 1.50 33. What is the hydraulic power of a pump that adds 550-feet of pressure head to 100-Ib m/s of water? A. 200 Hp B. 100 Hp C. 150 Hp D. 175 Hp 34. Water at 60°F has a specific gravity of 0.999 gm/cm 3 and a kinematic viscosity of 1.12 centistoke (cs). What is the absolute viscosity in lbf -s/ ft 2? A. 2.34 x 10-5 B. 3.24 x 10 -5 C. 4.23 x 10 -5
D. 5.34 x 10 -5 35. What is the velocity of sound in 150°F water? The density is 61.2 Ib m/ft3 and the bulk modulus is 328,000 psi. A. 4968 ft/s B. 4895 ft/s C. 9486 ft/s D. 9846 ft/s 36. A jet of water issues from 100 mm diameter nozzle with a velocity of 20 m/s. Find the Hp of the jet. A. 42.1 Hp B. 34.2 Hp C. 43.2 Hp D. 32.1 Hp 37. What pressure drop (in mm Hg ) in the blood as it passes through a capillary 1 mm long and 2µm in radius if the speed of the blood through the center of the capillary is 0.66 mm/s considering that the viscosity of the blood is 4 x 10 -3 Pa.s? 2.6 kPa A. 1.5 kPa B. 2.5 kPa C. 3.5 kPa D. 31. At what critical speed, which the flow of water in a long cylindrical pipe of diameter 2 cm, becomes turbulent considering that the temperature is 20°C, viscosity is 1.0 x 10 3 Pa.s, and critical Reynold ’s number is 3000. 0.350 m/s A. 0.250 m/s B. 0.234 m/s C. 0.150 m/s D. 39. A hole of area 1 mm 2 opens in the pipe near the lower end of a large water - storage tank, and a steam of water shoots from it. If the top of the water in the tank is 20 m above the point of the leak, how much water escapes in 1-s? 18.76 mL/s A. 17.78 mL/s B. 17.65 mL/s C. 19.80 mL/s D. 40. Two plates separated by a SAE 30 fluid, 0.3 mm thick. If the upper is moved with a velocity of 1 m/s, what is the surface resistance of 1-m2 upper plate it the viscosity is µ= 9.6 x 10 -2 N-s/m 2. 230 N A. 120 N B. 420 N C. 320 N D. 41. EE Board Problem APRIL 1995 A wooden spherical ball with sp. gr. of 0.42 and a diameter of 30 cm dropped from a height of 4.2 m above the surface of the eater in a pool. If the ball barely touches the bottom of the pool before it begun to float, how deep is the water in the pool at that point? A. 3.40 m B. 3.19 m C. 3.91 m D. 2.39 m 42. EE Board October 1997 Find the mass flow rate of a liquid p 0.690 g/cm 3) flowing through a 5 cm (inside diameter) at 8.3 m/s. 69 kg/s A. 450 kg/s B. 11.24 kg/s C. 430 kg/s D. 43. EE Board October 1990 Water is flowing through a pipe of 0.60 m diameter and 2 km length. If the average velocity of water is 2 m/s, what is the loss of head due to friction considering that the friction factor is 0.005? 13.6 A. 12.7 B. 11.7 C. 9.7 D. 44. A hose shoots water straight up for a distance of 2.5 m. If the end opening of the hose has area of 0.75 cm 2, compute the speed of the speed of the water the moment the water leaves the hose. 6 m/s A. 9 m/s B. 5 m/s C. 7 m/s D. 45. A hole with area of 1-mm 2 opens in the pipe near the lower end of a large water-storage tank, and a stream of water shoots from it. If the top of the water in the tank is 20 m above the point of the leak, compute the volume of water that escapes in 1-second. 20.7 mL/s A. 19.8 mL/s B. 12.7 mL/s C. 10.3 mL/s D. 46. A water flows out of a pipe at the rate of 3 cm 3 /s. What is the velocity of the water at a point in the pipe where the diameter is
0.50? A. 14.42 cm/s B. 16.3 cm/s C. 15.27 cm/s D. 19.7 cm/s 47. Water pumped at 1-m 3/s to an elevation of 5-m through a flexible hose using 100% efficient pump rated at 100 kW. Using the same length of hose, what size if motor is needed to pump 1-m 3/s of water to a tank with no elevation gains? In both cases, both ends of hose are at atmospheric pressure. Neglect kinetic energy. A. 51 kW B. 38 kW C. 57 kW D. 72 kW 48. The flow rate of water through a cast iron pipe is 5000 gallons per minute. The pipe is 1-foot and the coefficient of friction, f = 0.0173. What is the pressure drop over the 100 feet length of the pipe? A. 337.8 lb/ft2 B. 398.8 lb/ft2 C. 475.9 lb/ft2 D. 547.3 Ib/ft2 49. A vacuum pump is used to drain a flooded mine shaft of 20°C water. The pump pressure of water at this temperature is 2.34 kPa. The pump is incapable of lifting the water higher than 10.16 m. What is the atmospheric pressure? A. 109.3 kPa B. 121.7 kPa C. 101.9 kPa D. 102.2 kPa 50. EE Board Nov. 2003 and April 2001 A sphere of radius 5 x 10 to the negative two cm and density of 1.1 g/cc falls at a constant velocity through a liquid of density 1.0 g/cc and viscosity of 1.00 poise. What is the velocity of the falling sphere cm/s? A. 0.0544 B. 0.4 C. 0.744 D. 1.53
