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A large storage tank, open to the atmosphere at the top and filled with water, develops a small hole in its side at a point 16.0 m below the water level. If the rate of flow from the leak is 2.50×10−3m3/min, determine the diameter of the hole.

Respuesta :

Answer:

1.74 × 10^-3 m ( 1.74 mm)

Explanation:

Using Torricelli"s equation to calculate the speed of water at the surface of the hole and assuming that the speed of water at the surface of the tank is zero

v ( speed of water at the surface of the hole) = √ 2g(h1 - h2) where h1 - h2 is the difference in height  which 16 m

v = √ 2×9.81×16 = 17.72 m/s

work done in ( m³/s) = 2.5 × 10^ -3 / 60 seconds = 4.2 × 10^-5 m³/s

work done = A × v

4.2 × 10^-5 = A × 17.72

4.2 × 10^-5 / 17.72 = A

2.37 × 10^-6 = A where A is assumed a circle ( πr²)

r = 2.37 × 10^-6 / π = √2.37 × 10^-6 / 3.142 = 0.869 × 10 ^ -3

diameter = 2r = 2 × 0.869 × 10^-7 = 1.74 × 10^-3 m

Answer:

The diameter of the hole is [tex]1.73 x10^{-3}m[/tex]

Explanation:

The velocity at the top of the tank is zero. As depth increases, velocity increases, thus, potential energy is equal to the kinetic energy at the hole level (16-meter depth).

Step 1: We calculate the velocity of water at the hole level

ρgh = ρv²/2

gh = v²/2 (striking the density of water out)

Therefore,

[tex]v=\sqrt{2gh}[/tex]

v² = (2)(9.81 m/s²)(16 m)

∴ v = 17.7 m/s (velocity of water at the hole level)

Step 2: We find the area of the hole itself.

[tex]Area=\frac{Volumetric flow rate}{(velocity)(time)}[/tex]

[tex]Area=\frac{2.50x10^{-3} m^{3}/min }{(17.7 m/s)(60 s)}[/tex]

[tex]Area=2.35x10^{-6} m^{2}[/tex]

Step 3: We calculate the diameter of the hole from its area.

[tex]Area=\frac{\pi D^{2} }{4}[/tex]

[tex]D=2\sqrt{\frac{A}{\pi} }[/tex]

[tex]D=2\sqrt{\frac{2.35x10^{-6} }{3.142} }[/tex]

∵ [tex]D=1.73x10^{-3} m[/tex]