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Fluid Mechanics part 2 28601101 1. A pipe whose diameter is 10in. is equipped with a pipe orifice. The diameter of the orifice is 6.00in. Also, piezometers that lead to a differential mercury gage are connected to the pipe 10.0in above the orifice and 5.6in below the orifice. If the drop in pressure head indicated by the gage at a certain instant is equivalent to 2.27 ft of water, the rate of discharge for the pipe, in gallons per minute is A. 950gpm B. 820gpm C. 700gpm D. 638gpm 2.A rectangular surface is placed in a vertical position in fresh water with its top and bottom edges horizontal, as indicated in Examination Figure 1. If the dimensions b and d of the immersed surface are 8.00ft and 12.00ft and the vertical distance h from the surface of the water to the top edge of the immersed surface is 10.00ft, the magnitude of the resultant force on one side of the immersed surface is A. 131,800lb. B. 95,800lb. C. 59,900lb. D. 35,900lb 3.b=27.0in, d=63.0in, and h 5.00ft. The static moment of the immersed rectangular surface with respect to an axis in the surface of the water, in feet to the third power, is A. 90.1ft^3 B. 83.2ft^3 C. 76.3ft^3 D. 59.1ft^3 4.A rectangular plate is immersed in waster in a vertical plane with its top and bottom edges horizontal. If b=3.00ft, d=7.00ft, and h=2.00ft, the vertical distance from the surface is A. 6.67ft B. 6.24ft C. 5.50ft D. 4.33ft 5.A trapezoid surface having the dimensions shown in information below is immersed in fresh water with its top edge horizontal and at the surface of the water. The resultant force on one side of the immersed surface is A. 2620lb B. 1872lb C. 1685lb D. 1497lb 6.The moment of inertia of the trapezoidal surface in Information below with respect to the surface of the water is A. 63.0ft^4 B. 36.0ft^4 C. 18.0ft^4 D. 12.0ft^4 7.The formula to determine the moment of inertia of a rectangular surface with respect to a horizontal line drawn through its centroid is______ where the surface's width runs parrallel to the line through the centroid. A. 1/6 width times height to the second power B. 1/16 width times height to third power C. 1/12 width times height to the second power 1/12 width times height to the third power 8.A symmetrical trapezoidal plate has the following dimension: The widths of the parallel sides are, respectively, 2.50ft and 4.50ft, the perpendicular distance between those sides is 1.50ft. The plate is submerged in a liquid in a vertical position with the parallel sided horizontal and the shorter parallel side at the top and exactly even with the surface of the liquid. The moment of inertia of the plate with respect to the surface of the water would be A. 2.39ft^4 B. 3.37ft^4 C. 3.39ft^4 D. 4.49ft^4 9.A new casr-iron pipe for conveying water from one reservoir to another has a diameter equal to 8in., and its length is 5400ft. The head tending to cause flow is 40.5ft. If the velocity head and minor losses of head can be neglected, the rate of discharge, in cubic feet per second, computed by using the Chezy-Darcy formula is A. 1.60 cfs B. 1.43 cfs C. 1.28 cfs D. 1.15 cfs 10.A symmetrical trapezoidal plate has the following dimensions. The widths of the parallel sides are, respectively, 2.50ft and 4.50ft. The perpendicular distance between those sides is 1.50ft. The plate is submerged in a liquid in a vertical position with the parallel sides horizontal and the shorter parallel side at the top and exactly in the surface of the liquid. The static moment of the plate with respect to the surface of the liquid will be A. 5.43cu ft B. 4.31cu ft C. 6.93cu ft D. 7.68 cu ft 11.The diameter of a new cast-iron pipe in which water is flowing is 6 in. and the estimated velocity is 5.83 fps. The friction factor, determined from Table 4 and expressed to four decimal places is A. 0.0239. B. 0.0236 C 0.0233. D. 0.0219 12.the pipe described in question 11 contains four 90 degree elbows and two Y’s. the sum of the minor losses in head caused by these fittings is? A 0.0239 B. 0.0236 C. 0.0233 D. 0.0219 13. In the Hazen-Williams formula, the value of the factor C for a certain pipe may be taken as 145. The diameter of the pipe is 16 in. its length is 6400 ft, and the head tending to cause flow is 52.oft. The rate of discharge for the pipe, in gallons per minute, is A. 4100gpm B. 3380gpm C. 2650gpm D. 1900gpm 14.A pipe with a diameter of 10in. expands to 24in. abruptly. What is the head loss due to expansion if the velocity in the smaller diameter section is 14fps and then 1.75fps farther down in the larger diameter section? A. 0.5ft B. 0.2ft C. 2.3ft D. 4.7ft 15.A rectangular surface is emmersed in fresh water in an inclined position with its top and bottom edges horizontal. If the length of the surface is 10.00ft and the width of the surface is 5.00ft, the magnitude of the resultant force on one face of the surface is A. 20,300lb B. 17,690lb C. 14,340lb D. 10,140lb 16.A new cast-iron pipe 14in. in diameter and 840ft long conveys water from a reservoir and discharges it into the air. The sum of the factors by which v^2/2g should be mulitplied to allow for minor losses of head is 1.6. If the head tending to cause flow is 4.20ft, the mean velocity in the pipe computed by the Chezy-Darcy formula is A. 4.23fps B. 4.09fps C. 4.02fps D. 3.91fps 17.The length of a cast-iron pipe is to be 4200ft, and the head causing flow is to be 12.6ft. After the pipe has been in service 5 years, it is expected to discharge water at a rate equal to 3.2cfs. If the chart in Figure 14 in the text is used, the diameter of the pipe should be A. 16in B 14in C 12in D 10in 18.The rate of discharge for a pipe whose diameter is 16in. is to be measured by means of a Venturi meter for which the diameter of the throat is 8.00in and the factor is 0.978. When a differential mercury gage is connected at the inlet and the throat of the meter, the vertical distance between the surfaces of the mercury in the two legs of the gage is 1.31ft. The rate of discharge for the pipe, in gallons pre minute, is A. 5769gpm B. 5520gpm C. 5280gpm D. 5160gpm 19.A Venturi meter is inserted in a pipe whose diameter is 12in. The diameter of the meter at its throat is 6in. and the factor C1 for the meter is 0.980 when a differential mercury gage is connected at the inlet and the throat of the meter, the vertical distance between the surfaces of the mercury in the two legs of the gage is 1.1 5ft. The specific gravity of mercury is 13.6. The rate of discharge from the pipe is A. 5.67cfs B. 6.29cfs C. 6.05cfs D. 6.80cfs 20. The rate of discharge for a liquid traveling through a 10in. diameter pipe is 6.5cfs. The mean velocity at which the liquid is traveling is A. 7.8fps B. 9.8fps C. 11.9fps D. 14.4fpsw