$\"\"$

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Radius of the Circular observation window is $\"\"$ .

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Window is vertically in a large water tank.

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$\"\"$ .

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Observe the figure:

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Consider the depth of the tank is $\"\"$ .

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The circle equation is $\"\"$ .

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Consider the center of the circular end of the tank is at origin.

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$\"\"$

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$\"\"$

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$\"\"$ .

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The horizontal length of the tank is $\"\"$ .

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Therefore, $\"\"$ .

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The $\"\"$ ranges from $\"\"$ to $\"\"$ .

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The fluid force is $\"\"$ .

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(a)

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Find the fluid force on circular window when it is 3 feet below the water surface.

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Thus $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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Integral formula: $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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(b)

\

Find the fluid force on circular window when it is $\"\"$ feet below the water surface.

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Thus $\"\"$ .

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$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$

\

$\"\"$ .

\

Fluid force on a circular plate is $\"\"$ .

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$\"\"$

\

(a) $\"\"$ .

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(b) Fluid force on a circular plate is $\"\"$ .