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fluid mechanics 28601101 part 2

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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

				
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