2.55 The sensitivity Sen of the manometer shown in Fig. P2.55
can be defined as
Three manometer fluids with the listed specific gravities S are
available: kerosene, S = 0.82; SAE 10 oil, S = 0.87; and normal
octane, S = 0.71. Whic
Obtain a photograph/image of a situation that can be analyzed
by use of the Bernoulli equation. Print this photo and write a brief
paragraph that describes the situation involved.
This is an open-ended student activ
Obtain a photograph/image of a situation in which Archimedess
principle is important. Print this photo and write a brief paragraph
that describes the situation involved.
This is an open-ended student activity for which student resp
2.69 The hydraulic cylinder shown in Fig. P2.69, with a 4-in.-
diameter piston, is advertised as being capable of providing a
force of F = 20 tons. If the piston has a design pressure (the
maximum pressure at which the cylinder should safely operate)
3.7 The Bernoulli equation is valid for steady, inviscid, incompressible flows with constant
acceleration of gravity. Consider flow on a planet where the acceleration of gravity varies with
g g 0 cz , where g 0 and c are constants.
2.137 A barge is 40 ft wide by 120 ft long. The weight of the barge and its cargo is denoted by
W. When in salt-free riverwater, it floats 0.25 ft deeper than when in seawater ( = 64 lb/ft ).
Find the weight W.
The supersoaker water gun shown in Fig. P3.35 can shoot
more than 30 ft in the horizontal direction. Estimate the minimum
pressure, p1, needed in the chamber in order to accomplish this.
List all assumptions and show all calculati
2.143 A not-too-honest citizen is thinking of making bogus gold bars by first making a hollow
iridium (S = 22.5) ingot and plating it with a thin layer of gold (S = 19.3) of negligible weight
and volume. The bogus bar is to have a mass of 100
2 .148 A submarine is modeled as a cylinder
with a length of 300 ft, a diameter of 50 ft, and a
conning tower as shown in Fig. P2.148. The
submarine can dive a distance of 50 ft from the
floating position in about 30 sec. Diving is
Sometimes it is difficult to open an exterior door of a building
because the air distribution system maintains a pressure difference
between the inside and outside of the building. Estimate how
big this pressure differen
2.153 A plastic glass has a square cross section measuring 2. in. on a side and is filled to within
1 in. of the top with water. The glass is placed in a level spot in a car with two opposite sides
parallel to the direction of travel. How fast
Obtain a photograph/image of a situation that involves a
confined flow for which the Bernoulli and continuity equations
are important. Print this photo and write a brief paragraph that
describes the situ
2.75 The container shown in Fig. P2.75 has square cross sections. Find the
vertical force on the horizontal surface, ABCD.
The vertical force on surface ABCD is equal to the weight of the
imaginary fluid above ABCD as show on the picture on the
Estimate the pressure on your hand when you hold it in the
stream of air coming from the air hose at a filling station. List
all assumptions and show calculations. Warning: Do not try this
experiment; it can be dangerous!
This is an open-en
Obtain a photograph/image of a situation in which the concept
of the stagnation pressure is important. Print this photo and
write a brief paragraph that describes the situation involved.
This is an open-ended student activity for which stud
Obtain a photograph/image of a situation in which the
hydrostatic force on a curved surface is important. Print this photo
and write a brief paragraph that describes the situation involved.
This is an open-ended student activity for whic
2.126 A l0-m-long log is stuck against a dam, as shown in Fig.
P2.126. Find the magnitudes and locations of both the
horizontal force and the vertical force of the water on the log in
terms of the diameter D. The center of the log is at the same
2.36 The U-tube manometer shown in Fig. P2.36 has two
fluids, water and oil (S = 0.80). Find the height difference
between the free water surface and the free oil surface with no
applied pressure difference.
GIVEN: Soil=0.8 in Fig. P2.
2.124 A step-in viewing window having the shape
of a half-cylinder is built into the side of a large
aquarium. See Fig. P2.124. Find the magnitude,
direction, and location of the net horizontal forces
on the viewi
2.41 Find the percentage difference in the readings
of the two identical U-tube manometers shown in
Fig. P2.41. Manometer 90 uses 90 C water and
manometer 30 uses 30 C water. Both have the
same applied pressure difference. Does this
2.58 Consider the cistern manometer shown in
Fig. P2.58. The scale is set up on the basis that
the cistern area A1 is infinite. However, A1 is
actually 50 times the internal cross-sectional area
A2 of the inclined tube. Find the percentage error
2.48 What is the specific gravity of the liquid in the left
leg of the U-tube manometer shown in Fig. P2.48?
GIVEN: Fig. P2.48
FIND: Specific gravity S of unknown fluid
Let h15 15cm
Apply manometer rule,
Patm w g h2
2.98 The Altus dam in Problem 2.97 is made of concrete with a
density of 150 lbm/ft3. The coefficient of friction between the base
of the dam and the foundation is 0.65. Is the dam likely to slide
downstream? Consider a unit length of the dam (b = 1 ft).
2.81 A tank contains 6 in. of oil (S = 0.82) above 6 in. of water (S = 1.00). Find the
force on the bottom of the tank. See Fig. P2.81.
Assume atmospheric pressure acts on outside of tank.
Pressure is constant at constant elevation in a stagnant
Obtain a photograph/image of a situation in which the use
of a manometer is important. Print this photo and write a brief
paragraph that describes the situation involved.
This is an open-ended student activity for which student re
2.119 In drilling for oil in the Gulf of Mexico, some divers
have to work at a depth of 1300 ft. (a) Assume that seawater
has a constant density of 64 lb/ft and compute the pressure
at this depth. The divers breathe a mixture of