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crono_
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Homework Statement
A lost shipping container is found resting on the ocean floor and completely submerged. The container is 6.3 m long, 2.1 m wide, and 2.6 m high. Salvage experts attach a spherical balloon to the top of the container and inflate it with air pumped down from the surface. When the balloon's radius is 1.8 m, the shipping container just begins to rise towards the surface. What is the mass of the container? Ignore the mass of the balloon and the air within it. Do not neglect the buoyant force exerted on the shipping container by the water. The density of seawater is 1025 kg/m3.
Container
L = 6.3 m
w = 2.1 m
h = 2.6 m
V = ?
Balloon / Air
r = 1.8 m
p = 1.29 kg / m3
V =
FB =
Water
p = 1025 kg / m3
FB =
Homework Equations
Archimedes' Principle
FB = Wfluid
Vcontainer = L * w * h
Vballoon = 4/3 [tex]\pi[/tex]r3
p = m / v
F = ma
The Attempt at a Solution
First I found the volumes for the container and the balloon.
Vcontainer = L * w * h
Vcontainer = 6.3 * 2.1 * 2.6
Vcontainer = 34.398 m3
Vballoon = 4/3 [tex]\pi[/tex]r3
Vballoon = 4/3 [tex]\pi[/tex]1.83
Vballoon = 24.429
I then tried to find the buoyant force of the air.
FB = Wair
FB = mg
FB = pVg
FB = 1.29 * 24.429 * 9.8
FB = 308.83 N
And then for the sea water.
FB = Wwater
FB = mg
FB = pVg
FB = 1025 * 34.398 * 9.8
FB = 345527.91 N
After this, I used Newton's 2nd law...
F = ma
m = F / a
m = FBair + FBwater / g
m = 308.83 N + 345527.91 N / 9.80 m/s2
m = 35289 kg ----> 3.5 * 104 kg
But...this appears to be wrong...Um...thoughts?
Thanks!
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