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Absolute and Gauge Pressure

A dam to create a large fresh water lake is constructed. It will be approximately 14 meters deep. A horizontal pipe 1.2 meters long and 4 cm in diameter will pass through the dam at a depth of 7 meters to allow for release of the water in emergencies and for sampling. In normal situations, a plug will secure the pipe opening.

(SEE THE ATTACHED PICTURE)

Pls explain the calculations in detail.

(a) What will be the total force on the left side of the plug?
F(left) = ____________________ N

(b) What is the total force on the right side of the plug?
F(right) = ____________________ N

(c) What is the gauge pressure on the plug?
Pgauge = ____________________ Pa

(d) If the plug were to be removed, how much water would flow out in 3 hours?
¦¤VOL = ____________________ m3

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Diameter of the pipe = 4 cm
Radius of the pipe = 2 cm or 0.02 m
Area of cross section of pipe = 3.14*0.02*.02
= 1.256*10^-3 m^2

(a) Hydrstatic pressure at a depth of 7 m = hdg
= 7*1000*9.8
= 6.86*10^4 N/m^2 or Pascal (Pa)
Total pressure = hydrostatic + atmospheric preuure
= 6.86*10^4 + 1.01*10^5
= 1.696*10^5 Pa
Pressure = Thrust / Area
Thrust or force acting normally on the left side of the plug = Pressure*Area
...

Solution Summary

The expert examines absolute and gauge pressure for a freshwater lake.

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