What is the force of water at the Mariana Trench and the weight of a jetliner?

AI Thread Summary
The Mariana Trench, at approximately 11,000 meters deep, exerts significant pressure on underwater vehicles, calculated using the formula P = pgh, where p is the seawater density (1025 kg/m^3) and h is the depth. The force on a vehicle's observation window with a radius of 0.1 m can be determined using the area and pressure relationship. For the weight of a jetliner with a mass of 1.2 x 10^5 kg, the force can be calculated using F = mg. Additionally, the discussion touches on blood flow in the human body, using the principle of conservation of flow rate to estimate the number of capillaries based on the aorta's dimensions. Overall, the conversation focuses on applying fluid dynamics principles to solve these physics problems.
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I'm having a lot of trouble with fluids I need some help on these two questions :/

the mariana trench is located in the floor of the Pacific Ocean at a depth of about 11 000 m below the surface of the water. The density of seawater is 1025 kg/m^3.
if an underwater vehicle were to explore such a depth, what force would the water exert on the vehicles observation window (radius=.10m)?
For comparison, determine the weight of a jetliner whose mass is 1.2x10^5 kg

The aorta carries blood away from the heart at a speed of 40 cm/s and has a radius of 1.1cm. The aorta branches eventually into a large number of tiny capillaries that distribute the blood to various organs. In a capillary, the blood speed is about .07 cm/s and the radius is about 6x10^-4cm. Treat the blood as an incompressible fluid, and use these data to determine the approximate number of capillaries in the human body

any help please? thanks a lot!
 
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Ok... I am new to this forum but I noticed your post and thought I'd lent a hand. I am enrolled in Advanced Placement Physics at my high school and we already went over fluids so I think i can help.

For your first question:

P = p*g*h
P = F/A
A = pi*r^2
--so--
F=P*A
--and--
F=p*g*h*pi*r^2

and the other part:

F = ma
--so--
Fg = m*g

For the second question:

It is flow rate...

AV(before) = AV(after)
A = pi*r^2
--so--
pi*r^2*V = pi*r^2*V

since there are multiple capilaries...

r(of aorta)^2*V(of a.)
------------------------ (divided by) = Number of capilaries
r(of capilaries)^2*V(of c.)

Hope this helped
 
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