Fluid Statics Review.pptx - Department of Civil Engineering

Civil Engineering Hydraulics
Mechanics of Fluids
Fluid Statics Review
Porphyrophobia is the fear of the color purple.
Manometer Problem
Freshwater and seawater flowing in parallel horizontal pipelines are
connected to each other by a double U-tube manometer as shown above.
The density of sea water is 1035 kg/m3. What is the ratio of the pressure in
the Seawater to the pressure in the Freshwater?
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Fluid Statics Review Questions
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Surface Pressure
The 500 kg load on the hydraulic lift is located as shown above. The fluid in
the system is oil with a mass density of 780 kg/m3. Assume both the tube on
the right and the cylinder on the left holding the weight have a circular cross
section. What is the height h?
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Fluid Statics Review Questions
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Surface Pressure
The flow of water is controlled by a 5ft wide hinged gate as shown above. It is
desired that the gate open when the depth of water is 12 feet. What must the
weight W be to keep the gate closed?
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Fluid Statics Review Questions
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Surface Pressure
The gate shown above has a width of 4 m and may be considered to be of
negligible weight. What force must be provided by the spring to keep the gate
closed?
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Fluid Statics Review Questions
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Surface Pressure
A cubic ice block is floating in seawater with has a specific gravity of 1.025.
The ice block has a specific gravity of 0.92. What is the distance h?
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Fluid Statics Review Questions
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Homework Problem 7-1
1. A gasoline line is connected to a pressure gage through a double-U tube
manometer as shown. If the reading of the pressure gage is 370 kPa,
determine the gage pressure of the gasoline line.
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Fluid Statics Review Questions
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Homework Problem 7-2
2. A semicircular 30-ft-diameter tunnel is to be built under a 150 ft deep, 800 ft
long lake as shown. Determine the total hydrostatic force acting on the roof of
the tunnel.
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Fluid Statics Review Questions
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Homework Problem 7-3
3. The water in a 25-m-deep reservoir is kept inside by a 150-m-wall whose
cross section is an equilateral triangle as shown above. Determine the total
force (hydrostatic+atmospheric) acting on the inner surface of the wall and its
line of action and determine the horizontal component of the force.
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Fluid Statics Review Questions
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